Name: align-items
-	Value: normal | stretch | <> | [ <>? <> ]
+	Value: normal | stretch | <> | <>? <>
 	Initial: normal
 	Applies to: all elements
 	Inherited: no
@@ -2064,7 +2070,7 @@ Row and Column Gutters: the 'row-gap' and 'column-gap' properties
 			see [[#gap-percent]].
 
 		: normal
-		:: The ''gap/normal'' represents
+		:: The value ''gap/normal'' represents
 			a used value of ''1em'' on multi-column containers,
 			and a used value of ''0px'' in all other contexts.
 	
@@ -2252,8 +2258,8 @@ Determining the Baselines of a Box
 		
block containers
 		

 			The first/last [=baseline set=] of a block container
-			is taken from the first/last in-flow line box in the block container
-			or the first/last in-flow block-level child in the block container
+			is taken from the first/last [=in-flow=] line box in the block container
+			or the first/last [=in-flow=] block-level child in the block container
 			that contributes a set of first/last baselines,
 			whichever comes first/last.
 			If there is no such line box or child,
@@ -2349,7 +2355,7 @@ Determining the Baselines of a Box
 			and ''vertical-rl'' if 'direction' is ''rtl''.
 
 	For the purposes of finding the baselines of a box,
-	it and all its in-flow descendants with a scrolling mechanism (see the 'overflow' property)
+	it and all its [=in-flow=] descendants with a scrolling mechanism (see the 'overflow' property)
 	must be considered as if scrolled to their initial scroll position.
 	Additionally,
 	if the position of a [=scroll container=]’s first/last baseline
@@ -2514,175 +2520,13 @@ Appendix A: Static Position Terminology
 

 Changes
 
-	Changes since the 17 February 2023 Working Draft include:
-	

-		
Made [=block containers=] default to ''safe'' alignment.
-			See [[#auto-safety-default]].
-			(Issue 8992)
-		
Made [=absolutely positioned boxes=] default to using a “smart” safe alignment
-			that allows unsafe overflow of the [=inset-modified containing block=]
-			while maintaining safety within the [=original containing block=].
-			See [[#auto-safety-position]].
-			(Issue 10316,
-			 Issue 9960)
-		
Make all the ''space-*'' keywords fallback to ''safe'' overflow.
-			(Issue 10154)
-		
Clearly define the interaction of overflowing [=content distribution=] and [=scroll containers=]
-			to not impact layout, but to only affect the extent of the [=scrollable overflow area=].
-			(Issue 4957)
-		
Only apply the special margin-edge baseline rule for [=scroll container=] [=block containers=]
-			when 'baseline-source' is its [=initial value=].
-			(Issue 8214)
-		
When synthesizing the baseline of an orthogonal-flow box,
-			make the assumed parallel [=writing mode=] sensitive to 'direction'.
-			(Issue 7775)
-			

-				
Otherwise,
-					assume either ''horizontal-tb'' or ''vertical-lr'' 'writing-mode',
-					whichever is orthogonal to the box’s own 'writing-mode'.
-				
Otherwise:
-					

-						
If the box’s own [=writing mode=] is vertical,
-							assume ''horizontal-tb''.
-						
If the box’s own [=writing mode=] is horizontal,
-							assume ''vertical-lr'' if 'direction' is ''ltr''
-							and ''vertical-rl'' if 'direction' is ''rtl''.
-					
-				
-			
-		
Clarify that spanning cells only participate in the first/last row they span
-			when participating in first/last baseline alignment.
-			(Issue 7655)
-		
Define the 'grid-gap' properties as [=legacy name aliases=] of the 'gap' properties.
-			(Issue 8014)
-		
Defer definition of ''align-self/normal'' alignment for [=absolutely positioned boxes=] to [[css-position-3]].
-			(Issue 11215,
-			 Issue 11285)
-		
Changed sentence about applicability of 'row-gap' to [=multi-column containers=]
-			to indicate that it applies in [[CSS-MULTICOL-2]].
-			(Issue 11539)
-		
Defined that [=gutters=] dissappear at [=fragmentation breaks=].
-			(Issue 11520)
-	
-
-	Changes since the 24 December 2021 Working Draft include:
-	

-		
Define the baselines of a [=multi-column container=].
-			(Issue 7856,
-			 Issue 7639)
-		
Use the [=writing mode=] of the [=static-position containing block=]
-			when determining the [=static position=].
-			(Issue 7599,
-			 Issue 7612;
-			 Changes)
-		
Remove definition of special behavior for including padding in [=scrollable overflow=]
-			for non-''align-content/normal'' alignments
-			since this is now defined unconditionally in [[!CSS-OVERFLOW-3]].
-			(Issue 129)
-		
Minor clarifications:
-			* Define [=fallback alignment=] of a [=baseline-sharing group=]
-				as the shared [=fallback alignment=] of its individual items.
-			* Annotate <> value definitions using [=CSS bracketed range notation=].
-	
-
-	Changes since the 21 April 2020 Working Draft include:
-	

-		
Allowed reordering of ''[ first | last ]'' and ''align-self/baseline'' components of <>.
-		(Issue 5235)
-		
Make [=fallback alignment=] of ''space-around'' and ''space-evenly'' include ''safe''.
-		(Issue 5088)
-		
Various corrections to normal alignment and percentage gaps
-		to match respective layout specs.
-		
Corrections to special legacy handling of the [=last baseline set=] of [=scroll containers=].
-		(Issue 3611)
-		
Clarify that a box with no [=baseline set=] synthesizes its [=alignment baseline=] as needed.
-		(Issue 3611)
-		
Clarified that only non-replaced boxes are affected by [=content distribution=].
-		(Issue 4545)
-		
Clarified when a box has a [=coordinated self-alignment preference=]
-		that enables [=baseline content-alignment=],
-		particularly with respect to ''margin/auto'' [=margins=].
-		(Issue 5923)
-		
Better define how baseline self-alignment and content-alignment interact.
-		(Issue 6389)
-		
Clarify how baseline-sharing groups determine their fallback alignment.
-		(Issue 7645)
-	
+	Changes since the 11 March 2025 Working Draft include:
+	* Clarify that [[#auto-safety-position]] applies when 'position-area' alters the [=used value=] of ''align-self/normal''.
+	* Allow absolutely positioned boxes to honor alignment even when overflowing into
+		the scrollable overflow area of a scroll container containing block.
+		(Issue 12106)
 
-	Changes since the 6 December 2018 Working Draft include:
-	

-		
Improved the center self-alignment of absolutely-positioned elements.
-		Issue 4659
-		
Fixed inconsistent fallback of baseline alignment in mixed writing modes.
-		Issue 3454
-		
Minor editorial fixes and clarifications.
-	
-
-	Changes since the 30 August 2018 Working Draft consist of some minor clarifications.
-
-	Changes since the 23 April 2018 Working Draft include:
-	

-		
Better definition of how the alignment properties interact with absolutely-positioned boxes with ''left/auto'' offsets.
-		See [[#justify-abspos]], [[#align-abspos]], [[#abspos-sizing]], and [[#staticpos-rect]].
-		
More detailed definition of how the content-distribution properties work on scroll containers.
-		See [[#overflow-scroll-position]].
-		
Noted CSS2’s special rules about the baselines of inline-block scroll containers.
-		
Defined that percentage gaps compute against zero when calculating intrinsic sizes, and resolve during layout. (Issue 509)
-		
Miscellaneous minor clarifications.
-	
-
-	Changes since the 6 September 2017 Working Draft include:
-	

-		
Added more illustrations! Many thanks to Melanie Richards for working through a difficult diagramming problem.
-		
Fixed errors in property definition table of 'gap' shorthand.
-		
Defining percentage gaps to resolve to zero when the containing block’s size depends on the gaps.
-		(Issue 509,
-		Issue 2297)
-		
Fixed errors in handling left and right in the grammars.
-		
Fixed discrepancy in ''align-content/space-align'' fallback alignment.
-		(Issue 2316)
-		
Tightened up handling of baseline alignment in cases where the box edges don't align.
-		(Issue 1556,
-		Issue 1611)
-		
Miscellaneous clarifications.
-	
-
-	Changes since the 20 July 2017 Working Draft include:
-	

-		
Added the 'row-gap' and 'column-gap' properties and 'gap' shorthand,
-			applying them to both grid layout and flex layout
-			to replace the grid-specific 'grid-row-gap'/'grid-column-gap'/'grid-gap' properties.
-	
-
-	Changes since the 15 May 2017 Working Draft include:
-	

-		
Dropped the ''left'' and ''right'' keywords from 'align-self' and 'align-content'.
-			They may be re-introduced in a later level if there is demand.
-			(Issue 1403)
-		
Assigned ''end'' fallback alignment to ''align-self/stretch'' cases when combined with ''last baseline'' content-alignment.
-		
Disabled baseline alignment across cells in a table column,
-			due to implementation complexity.
-		
A large number of minor corrections and clarifications reported by David Baron.
-	
-
-	Changes since the 7 April 2017 Working Draft include:
-	

-		
Adding a section to clarify handling of partial implementations.
-			(Issue 1167)
-		
Dropped <> value of 'justify-content' since it can't do anything anyway.
-			(Issue 1184)
-		
Deferred ability to specify fallback alignments to Level 4.
-			(Issue 1002)
-		
Fixed position of <> wrt <>.
-			(Issue 1001)
-		
Fixed rules for handling baseline-aligned boxes being aligned along their block axis.
-			(Issue 1038)
-		
Renamed ''justify-items: auto'' to ''justify-items: legacy''.
-			(Issue 1318)
-		
Clamped baselines of scrollable boxes to the border edge, rather than margin edge.
-			(Issue 766)
-		
Updated the flex container gap definition to use 'gutter'. (Issue 12084)
-	
+	See also previous changes.
 
 

 Privacy Considerations
diff --git a/css-anchor-position-1/Overview.bs b/css-anchor-position-1/Overview.bs
index 5c49434f9e9e..9abafa68c6e2 100644
--- a/css-anchor-position-1/Overview.bs
+++ b/css-anchor-position-1/Overview.bs
@@ -1,5 +1,5 @@
 
-Title: CSS Anchor Positioning
+Title: CSS Anchor Positioning Module Level 1
 Shortname: css-anchor-position
 Level: 1
 Status: ED
@@ -110,6 +110,23 @@ to find the “best” one that avoids overlap/overflow.
 		max-inline-size: 20em;
 	}
 	
+
+	Note that using the [[HTML#the-popover-attribute|Popover API]]
+	will automatically set 'position' and create the anchoring relationship
+	without setting 'anchor-name' or 'position-anchor' value
+	(by defining an [=implicit anchor element=]),
+	so those properties wouldn't need to be explicitly set again.
+	So with the correct markup, this example can be simplified to:
+
+	
+	.tooltip {
+		/* Using the popover + popovertarget attributes sets 'position: fixed'
+		   and creates the necessary position-anchor relationship already. */
+		position-area: block-start;
+		position-try: flip-block;
+		max-inline-size: 20em;
+	}
+	
 
 
 

@@ -156,7 +173,7 @@ Animation Type: discrete
 
 The 'anchor-name' property declares
 that an element is an anchor element,
-whose [=principal box=] is an anchor box,
+whose [=principal box=] is an [=anchor box=],
 and gives it a list of anchor names to be targeted by.
 Values are defined as follows:
 
@@ -168,7 +185,7 @@ Values are defined as follows:
 	:: If the element generates a [=principal box=],
 		the element is an [=anchor element=],
 		with a list of [=anchor names=] as specified.
-		Each [=anchor name=] is a [=tree-scoped name=].
+		Each [=anchor name=] is a [=tree-scoped name/loosely matched=] [=tree-scoped name=].
 
 		Otherwise, the property has no effect.
 
@@ -195,6 +212,11 @@ Note: While an element is in the [=skipped contents=] of another element
 it's not an [=acceptable anchor element=],
 effectively acting as if it had no names.
 
+Note: Positioned elements in [=shadow trees=]
+can reference [=anchor names=] defined in “higher” trees.
+Currently, they cannot reference [=anchor names=]
+defined in “lower” shadow trees, though.
+
 ### Implicit Anchor Elements ### {#implicit}
 
 Some specifications can define that,
@@ -214,20 +236,37 @@ The [=implicit anchor element=] of a [=pseudo-element=]
 is its [=originating element=],
 unless otherwise specified.
 
-### The Anchor's Position ### {#determining-position}
-
-Several features of this specification refer to the position and size of an [=anchor box=].
-The [=anchor box=]'s position and size is determined after layout,
-and for these purposes
-includes 'position'-based adjustments
-(such as ''position: relative'' or ''position: sticky'').
+### The Anchor Box ### {#anchor-position-size}
+
+Several features of this specification refer to the position and size of an anchor box.
+Unless otherwise specified,
+this refers to the [=border box=] edge of the [=principal box=] of the [=anchor element=].
+The [=anchor box=]'s position and size is determined after layout.
+
+This position and size includes 'zoom' and 'position'-based adjustments
+(such as ''position: relative'' or ''position: sticky'')
+as well as transforms (such as 'transform' or 'offset-path').
+In these cases, the axis-aligned bounding rectangle of the [=anchor box=]
+in the coordinate space of the [=absolutely positioned=] element's [=containing block=]
+is used instead.
+Transforms are often optimized onto a different thread,
+so transform-based updates to an [=anchor box’s=] position
+may be delayed by a few frames.
+Authors can avoid this delay by using absolute or relative positioning instead where practical.
+
+If the [=anchor box=] is [=fragmented=],
+and the [=containing block=] of the [=absolutely positioned=] box
+referring to that [=anchor box=] is outside the relevant [=fragmentation context=],
+the axis-aligned bounding rectangle of its [=box fragments=] is used instead.
+(If the [=absolutely positioned=] box is inside the [=fragmentation context=],
+it sees the [=anchor box=] as unfragmented--
+and can be itself fragmented by the [=fragmentation context=].)
 
-Post-layout effects, such as 'transform',
+For performance reasons,
+scrolling is handled specially, see [[#scroll]].
+Other post-layout effects, such as filters,
 do not affect the [=anchor box's=] position.
 
-Note: Allowing an anchor to opt into including the effects of 'transform'
-or similar properties
-might be allowed in the future.
 
 
-
-Centering on the Anchor: the ''anchor-center'' alignment value {#anchor-center}
---------------------------------------------------------------
-
-
-Name: justify-self, align-self, justify-items, align-items
-New Values: anchor-center
-
-
-The [=self-alignment properties=] allow an [=absolutely positioned box=]
-to align itself within the [=inset-modified containing block=].
-The existing values,
-plus carefully chosen [=inset properties=],
-are usually enough for useful alignment,
-but a common case for anchored positioning--
-centering over the [=anchor box=]--
-requires careful and somewhat complex set-up to achieve.
-
-The new anchor-center value
-makes this case extremely simple:
-if the positioned box has a [=default anchor box=],
-then it is centered (insofar as possible)
-over the [=default anchor box=]
-in the relevant axis.
-
-Additionally,
-any ''top/auto'' [=inset properties=] resolve to ''0''.
-
-If the box is not [=absolutely positioned=],
-or does not have a [=default anchor box=],
-this value behaves as ''/center''
-and has no additional effect on how [=inset properties=] resolve.
-
-Note: When using ''anchor-center'', by default
-if the anchor is too close to the edge of the box's
-[=original containing block=],
-it will “shift” from being purely centered,
-in order to remain within the [=original containing block=].
-See [[css-align-3#overflow-values]] for more details.
-
 
 
-Conditional Hiding: the 'position-visibility' property {#position-visibility}
-------------------------------------------------------
+Anchor-Based Alignment {#alignment}
+======================
 
-
-Name: position-visibility
-Value: always | [ anchors-valid || anchors-visible || no-overflow ]
-Initial: anchors-visible
-Applies to: [=absolutely positioned boxes=]
-Percentages: n/a
-Inherited: no
-Animation type: discrete
-
+

+Area-specific Default Alignment
 
-There are some conditions in which it might not make sense
-to display an [=absolutely positioned box=].
-This property allows such boxes to be made conditionally visible,
-depending on some commonly needed layout conditions.
+When 'position-area' is not ''position-area/none'',
+the [=used value=] of ''align-self/normal'' [=self-alignment=]
+changes depending on the <> value,
+to align the box towards the anchor:
 
-

-	: always
-	::
-		This property has no effect.
-		(The box is displayed without regard for its anchors
-		or its overflowing status.)
+* If the only the center track in an axis is selected,
+	the default alignment in that axis is ''align-self/center''.
+* If all three tracks are selected,
+	the default alignment in that axis is ''align-self/anchor-center''.
+* Otherwise, the default alignment in that axis
+	is toward the non-specified side track:
+	if it's specifying the “start” track of its axis,
+	the default alignment in that axis is ''align-self/end''; etc.
 
-	: anchors-valid
-	::
-		If any of the box's [=required anchor references=]
-		do not resolve to a [=target anchor element=],
-		the box's 'visibility' property computes to ''force-hidden''.
+However, if only one [=inset property=] in the relevant axis is ''inset/auto'',
+the default alignment is instead
+towards the edge with the non-''inset/auto'' inset;
+and this is an ''align-self/unsafe'' alignment.
 
-		Issue: What is a required anchor reference?
-		''anchor()'' functions that don't have a fallback value;
-		the default anchor *sometimes*?
-		Need more detail here.
+Note: This single-''inset/auto'' behavior preserves the way
+a single specified inset controls the position of an [=absolutely positioned=] box.
 
-		Issue: Any anchors are missing,
-		or all anchors are missing?
-		I can see use-cases for either, potentially.
-		Do we want to make a decision here, or make it controllable somehow?
+

+	For example, assuming an English-equivalent writing mode (horizontal-tb, ltr),
+	then the value ''span-x-start top'' resolves to
+	the ''position-area/start'' region of the vertical axis,
+	and the ''position-area/start'' and ''position-area/center'' regions of the horizontal axis,
+	so the default alignments will be ''align-self: end''
+	(making the box's bottom [=margin edge=] flush with the bottom of the ''position-area/top'' region)
+	and ''justify-self: end''
+	(making the box's end-side [=margin edge=] flush with the end side of the ''position-area/span-start'' region).
+
 
-	: anchors-visible
-	::
-		If the box has a [=default anchor box=]
-		but that [=anchor box=] is [=invisible=] or [=clipped by intervening boxes=],
-		the box's 'visibility' property computes to ''force-hidden''.
+

+	If the box overflows its [=inset-modified containing block=],
+	but would still fit within its [=original containing block=],
+	by default it will “shift” to stay within its [=original containing block=],
+	even if that violates its normal alignment.
+	See [[css-align-3#overflow-values]] for details.
 
-	: no-overflow
-	::
-		If the box overflows its [=inset-modified containing block=]
-		even after applying 'position-try',
-		the box's 'visibility' property computes to ''force-hidden''.
-
+	This behavior makes it more likely
+	that positioned boxes remain visible
+	and within their intended bounds,
+	even when their [=containing block=]
+	ends up smaller than anticipated.
 
-

-	An anchor box |anchor|
-	is clipped by intervening boxes
-	relative to a positioned box |abspos| relying on it
-	if |anchor|'s [=ink overflow rectangle=]
-	is fully clipped by a box
-	which is an ancestor of |anchor|
-	but a descendant of |abspos|'s containing block.
-	Clipping in this case refers only to clipping due to 'overflow',
-	or other effects (such as [=paint containment=])
-	that clip to the [=overflow clip edge=].
+	For example, a ''position-area: bottom span-right'' value
+	lets the positioned box stretch
+	from its anchor's left edge
+	to its containing block's right edge,
+	and left-aligns it in that space by default.
+	But if the positioned box is larger than that space
+	(such as if the anchor is very close to the right edge of the screen),
+	it will shift leftwards to stay visible.
+
 
-	Note: This means that if an abspos is next to its anchor in the DOM,
-	for example,
-	it'll remain visible even if its default anchor is scrolled off,
-	since it's clipped by the same scroller anyway.
 
-	Issue: Make sure this definition of clipped
-	is consistent with View Transitions,
-	which wants a similar concept.
+
+
+Centering on the Anchor: the ''anchor-center'' alignment value {#anchor-center}
+--------------------------------------------------------------
+
+
+Name: justify-self, align-self, justify-items, align-items
+New Values: anchor-center
+
+
+The [=self-alignment properties=] allow an [=absolutely positioned box=]
+to align itself within the [=inset-modified containing block=].
+The existing values,
+plus carefully chosen [=inset properties=],
+are usually enough for useful alignment,
+but a common case for anchored positioning--
+centering over the [=anchor box=]--
+requires careful and somewhat complex set-up to achieve.
+
+The new anchor-center value
+makes this case extremely simple:
+if the positioned box has a [=default anchor box=],
+then it is centered (insofar as possible)
+over the [=default anchor box=]
+in the relevant axis.
+Additionally:
+* The [=scrollable containing block=] is used in place of the [=local containing block=]
+	where applicable,
+	so that the entire [=scrollable overflow area=] (typically) is available
+	for positioning.
+* The [=used value=] of any ''top/auto'' [=inset properties=]
+	and ''margin/auto'' [=margin properties=]
+	resolves to ''0''.
+
+If the box is not [=absolutely positioned=],
+or does not have a [=default anchor box=],
+this value behaves as ''/center''
+and has no additional effect on how [=inset properties=] resolve.
+
+Note: When using ''anchor-center'', by default
+if the anchor is too close to the edge of the box's
+[=original containing block=],
+it will “shift” from being purely centered,
+in order to remain within the [=original containing block=].
+See [[css-align-3#overflow-values]] for more details.
 
 
 
 Anchor-Based Sizing {#sizing}
@@ -1458,10 +1404,10 @@ is equivalent to ''width: anchor-size(width)''.)
 An ''anchor-size()'' function representing a [=resolvable anchor-size function=]
 resolves at [=computed value=] time
 (via [=style & layout interleaving=])
-to the <> separating the relevant border edges
+to the <> separating the relevant edges
 (either left and right, or top and bottom,
 whichever is in the specified axis)
-of the [=target anchor element=].
+of the [=target anchor element's=] [=anchor box=].
 
 
 

@@ -1526,7 +1472,7 @@ Giving Fallback Options: the 'position-try-fallbacks' property {#position-try-fa
 
 
 Name: position-try-fallbacks
-Value: none | [ [<> || <>] | <<'position-area'>> ]#
+Value: none | [ [<> || <>] | <> ]#
 Initial: none
 Inherited: no
 Applies to: [=absolutely positioned boxes=]
@@ -1537,7 +1483,8 @@ This property provides a list of alternate positioning styles
 to try when the [=absolutely positioned box=]
 overflows its [=inset-modified containing block=].
 This position options list
-is initially empty.
+initially contains a single [=position option=]
+generated from the element's base styles.
 
 Each comma-separated entry in the list is a separate option:
 either the name of a ''@position-try'' block,
@@ -1572,7 +1519,7 @@ Values have the following meanings:
 		and adds it to the [=position options list=].
 
 		
-		<> = flip-block || flip-inline || flip-start
+		<> = flip-block || flip-inline || flip-start || flip-x || flip-y
 		
 
 		: flip-block
@@ -1586,6 +1533,17 @@ Values have the following meanings:
 			swaps the values in the [=inline axis=],
 			essentially mirroring across a [=block-axis=] line.
 
+		: flip-x
+		::
+			swaps the values in the [=horizontal axis=]
+			(between, for example, 'margin-left' and 'margin-right'),
+			essentially mirroring across a [=vertical-axis=] line.
+
+		: flip-y
+		::
+			swaps the values in the [=vertical axis=],
+			essentially mirroring across a [=horizontal-axis=] line.
+
 		: flip-start
 		::
 			swaps the values of the [=start=] properties with each other,
@@ -1599,6 +1557,8 @@ Values have the following meanings:
 		If multiple keywords are given,
 		the transformations are composed in order
 		to produce a single [=position option=].
+		Logical directions are resolved against
+		the [=writing mode=] of the [=containing block=].
 
 	: <> || <>
 	::
@@ -1612,7 +1572,7 @@ Values have the following meanings:
 
 		Otherwise, does nothing.
 
-	: <<'position-area'>>
+	: <>
 	::
 		Automatically creates a [=position option=]
 		composed solely of a 'position-area' property
@@ -1925,7 +1885,7 @@ The syntax of the ''@position-try'' rule is:
 The <> specified in the prelude
 is the rule's name.
 If multiple ''@position-try'' rules are declared with the same name,
-the last one in document order "wins".
+they [=cascade=] the same as ''@keyframe'' rules do.
 
 The ''@position-try'' rule only accepts
 the following [=properties=]:
@@ -2002,7 +1962,7 @@ Applying Position Fallback {#fallback-apply}
 When a positioned box
 (shifted by its [=default scroll shift=])
 overflows its [=inset-modified containing block=],
-and has a non-empty [=position options list=],
+and has more than one [=position option=] in its [=position options list=],
 it [=determines position fallback styles=]
 to attempt to find an option that avoids overflow.
 
@@ -2011,6 +1971,10 @@ so they affect [=computed values=]
 (and can trigger transitions/etc)
 even though they depend on layout and [=used values=].
 
+ISSUE: Rewrite this section to be less confusing and more correct.
+See Issue 12818,
+Issue 12890.
+
 

 	To apply a position option to a box's element |el|,
 	given a [=position option=] |new styles|:
@@ -2098,18 +2062,16 @@ laying out later boxes cannot change this decision.
 

 	At the time that {{ResizeObserver}} events are determined and delivered:
 
-	* If a box |el| is [=absolutely positioned=],
-		set its last successful position option
-		to the set of [=accepted @position-try properties=] (and values)
-		that it's currently using.
+	* If |el| has a [=last successful position option=]
+		remove its [=last successful position option=]
+		if any of the following are true:
 
-	* Otherwise, if |el| has a [=last successful position option=]
-		and if any of the following are true of it,
-		remove its [=last successful position option=]:
-
-		* |el| is not [=absolutely positioned=]
-		* |el|'s computed value for 'position-try-fallbacks' has changed
-		* Any of the ''@position-try'' rules referenced by |el|'s 'position-try-fallbacks'
+		* Its computed 'position' value has changed,
+			its [=containing block=] association has changed,
+			or it no longer generates a box.
+		* Its computed value for any [=longhand property|longhand=] of 'position-try' has changed.
+		* Its computed value for any [=accepted @position-try property=] has changed.
+		* Any of the ''@position-try'' rules referenced by it
 			have been added, removed, or mutated.
 
 		Then, [=determine position fallback styles=] for |el|
@@ -2117,6 +2079,11 @@ laying out later boxes cannot change this decision.
 		to the set of [=accepted @position-try properties=] (and values)
 		that it's now using.
 
+	* Otherwise, if a box |el| is [=absolutely positioned=],
+		set its last successful position option
+		to the set of [=accepted @position-try properties=] (and values)
+		that it's currently using.
+
 	Note: The timing of this recording/removal
 	is intentionally identical to the treatment of [=last remembered sizes=].
 
@@ -2151,6 +2118,110 @@ This limit must be at least five.
 
 
 
+
+
+
+Conditional Hiding: the 'position-visibility' property {#position-visibility}
+------------------------------------------------------
+
+
+Name: position-visibility
+Value: always | [ anchors-valid || anchors-visible || no-overflow ]
+Initial: anchors-visible
+Applies to: [=absolutely positioned boxes=]
+Percentages: n/a
+Inherited: no
+Animation type: discrete
+
+
+There are some conditions in which it might not make sense
+to display an [=absolutely positioned box=].
+This property allows such boxes to be made conditionally visible,
+depending on some commonly needed layout conditions.
+
+

+	: always
+	::
+		This property has no effect.
+		(The box is displayed without regard for its anchors
+		or its overflowing status.)
+
+	: anchors-valid
+	::
+		If any of the box's [=required anchor references=]
+		do not resolve to a [=target anchor element=],
+		the box's 'visibility' property computes to ''force-hidden''.
+
+		Issue: What is a required anchor reference?
+		''anchor()'' functions that don't have a fallback value;
+		the default anchor *sometimes*?
+		Need more detail here.
+
+		Issue: Any anchors are missing,
+		or all anchors are missing?
+		I can see use-cases for either, potentially.
+		Do we want to make a decision here, or make it controllable somehow?
+
+	: anchors-visible
+	::
+		If the box has a [=default anchor box=]
+		but that [=anchor box=] is [=invisible=] or [=clipped by intervening boxes=],
+		the box's 'visibility' property computes to ''force-hidden''.
+
+	: no-overflow
+	::
+		If the box overflows its [=inset-modified containing block=]
+		even after applying 'position-try',
+		the box's 'visibility' property computes to ''force-hidden''.
+
+
+

+	An anchor box |anchor|
+	is clipped by intervening boxes
+	relative to a positioned box |abspos| relying on it
+	if |anchor|'s [=ink overflow rectangle=]
+	is fully clipped by a box
+	which is an ancestor of |anchor|
+	but a descendant of |abspos|'s containing block.
+	Clipping in this case refers only to the same clipping effects
+	that are (by default) checked by {{IntersectionObserver}},
+	i.e. clipping due to 'clip-path',
+	'overflow', or other effects (such as [=paint containment=])
+	that clip to the [=overflow clip edge=].
+
+	Whether or not |anchor| is [=clipped by intervening boxes=]
+	must be checked after [=updating content relevancy for a document=]
+	(see 'content-visibility' in [[css-contain-2]])
+	and running any {{ResizeObserver}},
+	but before running any {{IntersectionObserver}}.
+	It may also be checked at other times to improve responsiveness.
+	
+
+	Note: This means that if an abspos is next to its anchor in the DOM,
+	for example,
+	it'll remain visible even if its default anchor is scrolled off,
+	since it's clipped by the same scroller anyway.
+
+	Issue: Make sure this definition of clipped
+	is consistent with View Transitions,
+	which wants a similar concept.
+
+	Note: This ensures that in a “chained anchor” situation,
+	if the first abspos is hidden due to this property
+	(due to its anchor being scrolled off),
+	then another abspos using it as an anchor will also be hidden,
+	rather than also floating in a nonsensical location.
+
+
 
 
@@ -372,7 +371,7 @@ Declaring Keyframes
 		the state of the animation if it were given a duration of ''10s''.
 
 		

-			
+			
 			
 		
 	
@@ -1082,7 +1081,7 @@ Attributes
 			  
The declared declarations in the rule, in specified
 			      order.
 			  
parent CSS rule
-			  
The context object (i.e. this {{CSSKeyframeRule}}).
+			  
The context object (i.e. this {{CSSKeyframeRule}}).
 			  
owner node
 			  
Null.
 			
diff --git a/css-animations-2/Overview.bs b/css-animations-2/Overview.bs
index 647e64b169d1..bc6fb0839acf 100644
--- a/css-animations-2/Overview.bs
+++ b/css-animations-2/Overview.bs
@@ -17,7 +17,7 @@
 
 
 
-Title: CSS Animations Level 2
+Title: CSS Animations Module Level 2
 Status: ED
 Work Status: Exploring
 Shortname: css-animations
@@ -189,7 +189,7 @@ is elem. animation is disassociated from
 
 elem.style.animation = 'spin 1s';
 let animation = elem.getAnimations()[0]; // animation's owning element is elem
-elem.style.animation = ''; // animation no longer has an owning element
+elem.style.animation = ""; // animation no longer has an owning element
 
 
 Note that although the owning element is often equal to the
@@ -704,79 +704,263 @@ When multiple 'animation-*' properties are set simultaneously,
 so e.g. a change to 'animation-play-state' applies
 to the simultaneously-applied timeline specified in 'animation-timeline'.
 
+
+

+The 'animation-trigger' property
+
+
+Name: animation-trigger
+Value: [ none | [ <> <>+ ]+ ]#
+Initial: none
+Applies to: all elements
+Inherited: no
+Percentages: N/A
+Computed value: as specified
+Animation type: not animatable
+Canonical order: per grammar
+
+
+The 'animation-trigger' property
+specifies whether the animation is a [=triggered animation=],
+and if it is,
+what trigger it responds to
+and what actions it takes in response.
+'animation-trigger' is a [=reset-only sub-property=] of the 'animation' shorthand.
+Its values are:
+
+

+    : none
+    ::
+        The corresponding animation is not a [=triggered animation=].
+
+    : [ <> <>+ ]+
+    ::
+        The corresponding animation is a [=triggered animation=],
+        responding to the triggers named by each <>,
+        and responding by taking the action named by the corresponding <>.
+        (See [[#trigger-scope]] for how <>s are resolved to [=triggers=].)
+
+        How many <>s a trigger accepts,
+        and what exactly activates them,
+        is determined by the type of the trigger.
+        ([=Event triggers=] take one and possibly an optional second, depending on whether they're stateless or stateful;
+        [=timeline triggers=] take one and optionally a second.)
+        Specifying the wrong number of actions
+        (too many or too few)
+        is valid syntactically,
+        but causes the trigger to have no effect.
+
+        If multiple triggers occur simultaneously,
+        they take effect in the order specified.
+
+        If the same <> is specified multiple times,
+        all but the last have no effect.
+
+
+The possible <> values,
+and what effect they have in each animation state:
+
+
+    
+        
+    
+
Keyword
Extra Effect
initial
playing
paused
finished
+    
none
—
—
—
—
—
+    
play
—
{{play()}}
—
{{play()}}
{{play()}}
+    
play-forwards
set playback rate to positive
{{play()}}
—
{{play()}}
{{play()}}
+    
play-backwards
set playback rate to negative
{{play()}}
—
{{play()}}
{{play()}}
+    
pause
—
—
{{pause()}}
—
—
+    
reset
set progress to 0
—
{{pause()}}
{{pause()}}
{{pause()}}
+    
replay
set progress to 0
{{play()}}
—
{{play()}}
{{play()}}
+    

+        If there is an "effect",
+        it happens regardless of the current state,
+        before the state-specific action
+    
+
+
 ## The 'animation' shorthand property ## {#animation-shorthand}
 
 The 'animation' shorthand property syntax is as follows:
 
 <single-animation> = <<'animation-duration'>> || <> || <<'animation-delay'>> || <> || <> || <> || <> || [ none | <> ] || <>
 
-

-Declaring Animation Triggers
-
-    Animation Triggers are defined using the 'animation-trigger-*' properties.
-    These list-valued properties,
-    which are all [=longhands=] of the 'animation-trigger' [=shorthand=],
-    form a [=coordinating list property group=]
-    with 'animation-name' as the [=coordinating list base property=]
-    and each item in the [=coordinated value list=]
-    defining the properties of a single animation trigger.
-
-    The 'animation-trigger' properties
-    are [=reset-only sub-properties=] of the 'animation' [=shorthand=].
 
-## The 'animation-trigger-behavior' property ## {#animation-trigger-behavior}
+
 
-
-Name: animation-trigger-behavior
-Value: <>#
-Initial: once
+

+Triggers
+
+While CSS animations are, by default,
+automatically run as soon as the appropriate 'animation' values have been set on an element,
+the 'animation-trigger' property allows the animation's start to be delayed
+until an appropriate trigger occurs,
+and even paused, restarted, or reset by triggers
+(making it a triggered animation).
+
+This is a simplified and streamlined version
+of what can be achieved with the Web Animations API in Javascript,
+allowing simple, common interaction patterns
+to be created and managed purely in CSS.
+
+Currently, two types of triggers are defined:
+
+* [=timeline triggers=], managed by the 'timeline-trigger' properties,
+    which allow animations to be triggered by entering or leaving certain timeline ranges.
+    (Usually, [=view progress timelines=],
+    so an animation can be started when an element comes on-screen,
+    without actually driving the animation with the scroll progress.)
+
+* [=event triggers=], managed by the 'event-trigger' properties,
+    which allow animations to be triggered by certain user-interaction events,
+    such as clicking an element or pressing certain keys.
+
+A [=trigger=] is defined on some specific triggering element.
+All triggers have a name,
+and the specific type of trigger dictates how and when it's activated.
+A trigger can define multiple "types" of activation.
+(For example, [=timeline triggers=] can do different things on entry and exit.)
+
+A [=trigger=] is used on potentially any element,
+creating a trigger instance on the element.
+(For example, 'animation-trigger' associates a [=trigger instance=]
+with a specific animation on the element.)
+The trigger-using element specifies what actions to take
+when the [=trigger=] activates.
+
+Note: This design for [=triggers=] and [=trigger instances=],
+and the way they're associated with [=triggered animations=] and <>s,
+is intentionally somewhat generic,
+intended to support using [=triggers=] for other purposes in the future.
+For now, though, [=triggered animations=] are the only user of this feature.
+
+
+

+Trigger Scope/Resolution
+
+All [=triggers=] are document-global by default,
+similar to [=anchor names=].
+
+If a single element attempts to define multiple [=triggers=] of different types
+with the same name,
+it only exposes one of them,
+with [=event triggers=] winning over [=timeline triggers=].
+
+Note: This order is completely arbitrary
+(based on alphabetic order of the concept name),
+as this is just an error case.
+
+If multiple elements define [=triggers=] with the same name,
+the [=trigger=] defined by the later element in [=tree order=] is used.
+
+Note: This behavior will be improved by a trigger-scope property,
+not yet defined,
+letting you define triggers that are only visible to subtrees
+and references that only search in that subtree
+(just like 'anchor-scope').
+
+
+
+

+Timeline Triggers
+
+A timeline trigger is a [=trigger=]
+which is activated when some [=timeline=]
+enters the trigger's enter range,
+or leaves the trigger's exit range.
+It is defined on an element with the 'timeline-trigger' shorthand property,
+or its longhands.
+
+A [=timeline trigger=] has a binary trigger state associated with it;
+it is initially "untriggered".
+While it's "untriggered",
+the associated [=timeline=] entering (or starting in) the trigger's [=enter range=]
+performs an associated enter action
+and switches the [=timeline trigger/trigger state=] to "triggered";
+while it's "triggered",
+the associated timeline leaving the trigger's [=exit range=]
+performs an associated exit action
+and switches the [=timeline trigger/trigger state=] to "untriggered".
+
+Note: By default, the [=exit range=] is the same as the [=enter range=];
+even when manually specified,
+the [=exit range=] is always a superset of the [=enter range=].
+The two ranges allow, for example,
+an 'animation-trigger' to start an animation
+when an element is scrolled close the center of the screen
+(using a [=view progress timeline=] with a relatively small window as the [=enter range=]),
+but not stop it until the element is fully off-screen
+(using ''animation-timeline-range/cover'' as the [=exit range=]).
+
+Issue: I think it's WebAnim2 that needs to define
+that exit ranges are interpreted
+as the bounding range of the [=enter range=]
+and what's specified for the [=exit range=].
+
+A [=timeline trigger=] can have one or two actions associated with it
+when used as a trigger on an element
+(such as by 'animation-trigger').
+If two are specified, the first is the trigger's [=timeline trigger/enter action=]
+and the second is the trigger's [=timeline trigger/exit action=];
+if only one is specified, the first is the trigger's [=timeline trigger/enter action=]
+and its [=timeline trigger/exit action=] is to do nothing.
+
+An element can define multiple [=timeline triggers=],
+using the same [=timeline=] (potentially with different ranges)
+or different ones.
+The set of 'timeline-trigger' longhands
+form a [=coordinating list property group=],
+with 'timeline-trigger-name' as the [=coordinating list base property=],
+and each item in the [=coordinated value list=]
+defining the properties of a single [=timeline trigger=].
+
+
+

+Naming the Trigger: the 'timeline-trigger-name' property
+
+
+Name: timeline-trigger-name
+Value: none | <>#
+Initial: none
 Applies to: all elements
 Inherited: no
 Percentages: N/A
-Computed value: list, each item a keyword as specified
-Animation type: not animatable
+Computed value: as specified
 Canonical order: per grammar
+Animation type: not animatable
 
 
-<single-animation-trigger-behavior> = once | repeat | alternate | state
-
-The values of 'animation-trigger-behavior' have the following meaning
-for an [=animation trigger=] that enters its [=animation trigger/active interval|active interval=]:
-
-

-        
once
-        

-                The animation is triggered and played once and only once.
-
-        
repeat
-        

-                The animation is played from the beginning each time it is triggered.
-                When the trigger’s [=animation trigger/active interval=] is exited the animation is reset.
+If ''timeline-trigger-name/none'' is specified,
+the element does not define any [=timeline triggers=].
 
-        
alternate
-        

-                The animation is played forwards, according to its [=playback direction=], each time it is triggered.
-                When the trigger’s [=animation trigger/active interval=] is exited the animation is reversed.
+If the same <> appears multiple times in the list,
+only the last one defines a [=timeline trigger=];
+the preceding ones have no effect.
 
-        
state
-        

-                The animation is triggered and played once.
-                When the trigger’s [=animation trigger/active interval=] is exited the animation is paused.
-                When the trigger’s [=animation trigger/active interval=] is re-entered the animation is resumed.
-
-
-The behavior of each value is defined in [[web-animations-2#trigger-behaviors]].
-
-## The 'animation-trigger-timeline' property ## {#animation-trigger-timeline}
 
-The 'animation-trigger-timeline' property specifies the timeline
-of the animation’s associated [=animation trigger=].
+

+Linking a Timeline: the 'timeline-trigger-source' property
 
 
-Name: animation-trigger-timeline
+Name: timeline-trigger-source
 Value: <>#
 Initial: auto
 Applies to: all elements
@@ -793,199 +977,266 @@ Canonical order: per grammar
 Animation Type: not animatable
 
 
-The values of 'animation-trigger-timeline' have the same meaning as those of 'animation-timeline'.
+The 'timeline-trigger-source' property
+specifies the [=timeline trigger's=] associated [=timeline=].
+Values have the same meaning as those of 'animation-timeline',
+except that ''timeline-trigger-source/none''
+instead causes the corresponding entry in the [=coordinated value list=]
+to not define a [=timeline trigger=].
 
-Issue: Probably a trigger with timeline "none" is under-specified here. Need to clarify what it means.
-
-## The 'animation-trigger-range' property ## {#animation-trigger-range}
+

+The Enter Range: the 'timeline-trigger-range' property
 
 
-  Name: animation-trigger-range
-  Value: [ <<'animation-trigger-range-start'>> <<'animation-trigger-range-end'>>? ]#
+Name: timeline-trigger-range
+Value: [ <<'timeline-trigger-range-start'>> <<'timeline-trigger-range-end'>>? ]#
 
 
-The 'animation-trigger-range' property is a [=shorthand property|shorthand=]
-that sets 'animation-trigger-range-start' and 'animation-trigger-range-end'
-together in a single declaration,
-specifying the [=animation trigger=]’s associated [=default range=].
+The 'timeline-trigger-range' property is a [=shorthand property=]
+that sets 'timeline-trigger-range-start' and 'timeline-trigger-range-end'
+together in a single declaration.
 It has the same syntax as the 'animation-range' property.
 
-The behavior of 'animation-trigger-range' is defined in [[web-animations-2#trigger-ranges]].
+The behavior of 'timeline-trigger-range' is defined in [[web-animations-2#trigger-ranges]].
 
-## The 'animation-trigger-range-start' property ## {#animation-trigger-range-start}
+Issue: Need to rewrite WebAnim2 to use the term "enter range".
 
 
-  Name: animation-trigger-range-start
-  Value: [ normal | <> | <> <>? ]#
-  Initial: normal
-  Applies to: all elements
-  Inherited: no
-  Percentages: relative to the specified [=named timeline range=] if one was specified, else to the entire timeline
-  Computed value: list, each item either the keyword ''animation-trigger-range-start/normal'' or a timeline range and progress percentage
-  Animation type: not animatable
+Name: timeline-trigger-range-start, timeline-trigger-range-end
+Value: [ normal | <> | <> <>? ]#
+Initial: normal
+Applies to: all elements
+Inherited: no
+Percentages: relative to the specified [=named timeline range=] if one was specified, else to the entire timeline
+Computed value: list, each item either the keyword ''animation-trigger-range-start/normal'' or a timeline range and progress percentage
+Animation type: not animatable
 
 
-The 'animation-trigger-range-start' property specifies the start of the [=animation trigger=]’s
-associated [=default range=].
+The 'timeline-trigger-range-start' and 'timeline-trigger-range-end' properties
+specify the [=timeline trigger=]’s associated [=timeline trigger/enter range=].
+Values have the same meaning as 'animation-range-start' and 'animation-range-end'.
 
-The values of 'animation-trigger-range-start' have the same meaning as those of 'animation-range-start'.
 
-## The 'animation-trigger-range-end' property ## {#animation-trigger-range-end}
+

+The Exit Range: the 'timeline-trigger-exit-range' property
 
-
-  Name: animation-trigger-range-end
-  Value: [ normal | <> | <> <>? ]#
-  Initial: normal
-  Applies to: all elements
-  Inherited: no
-  Percentages: relative to the specified [=named timeline range=] if one was specified, else to the entire timeline
-  Computed value: list, each item either the keyword ''animation-trigger-range-end/normal'' or a timeline range and progress percentage
-  Animation type: not animatable
+
+Name: timeline-trigger-exit-range
+Value: [ <<'timeline-trigger-exit-range-start'>> <<'timeline-trigger-exit-range-end'>>? ]#
 
 
-The 'animation-trigger-range-end' property specifies the end of the [=animation trigger=]’s
-associated [=default range=].
+The 'timeline-trigger-exit-range' property is a [=shorthand property=]
+that sets 'timeline-trigger-exit-range-start' and 'timeline-trigger-exit-range-end'
+together in a single declaration.
+It has the same syntax as the 'animation-range' property.
 
-The values of 'animation-trigger-range-end' have the same meaning as those of 'animation-range-end'.
+The behavior of 'timeline-trigger-exit-range' is defined in [[web-animations-2#trigger-ranges]].
 
-## The 'animation-trigger-exit-range' property ## {#animation-trigger-exit-range}
+
+
+Name: timeline-trigger-exit-range-start, timeline-trigger-exit-range-end
+Value: [ auto | normal | <> | <> <>? ]#
+Initial: auto
+Applies to: all elements
+Inherited: no
+Percentages: relative to the specified [=named timeline range=] if one was specified, else to the entire timeline
+Computed value: list, each item either the keyword ''animation-trigger-range-start/normal'' or a timeline range and progress percentage
+Animation type: not animatable
+
+
+The 'timeline-trigger-exit-range-start' and 'timeline-trigger-exit-range-end' properties
+specify the [=timeline trigger=]’s associated [=timeline trigger/exit range=].
+Values have the same meaning as 'animation-range-start' and 'animation-range-end',
+with the following addition:
+
+

+    : auto
+    ::
+        The start (for 'timeline-trigger-exit-range-start')
+        or end (for 'timeline-trigger-exit-range-end')
+        is equal to the start/end of the [=timeline trigger's=] [=enter range=].
+
+
+

+The 'timeline-trigger' Shorthand
 
 
-  Name: animation-trigger-exit-range
-  Value: [ <<'animation-trigger-exit-range-start'>> <<'animation-trigger-exit-range-end'>>? ]#
+Name: timeline-trigger
+Value: none | [ <<'timeline-trigger-name'>> <<'timeline-trigger-source'>> <<'timeline-trigger-range'>> [ '/' <<'timeline-trigger-exit-range'>> ]? ]#
 
 
-The 'animation-trigger-exit-range' property is a [=shorthand property|shorthand=]
-that sets 'animation-trigger-exit-range-start' and 'animation-trigger-exit-range-end'
-together in a single declaration,
-specifying the [=animation trigger=]’s associated [=exit range=].
-It has the same syntax as the 'animation-range' property, with the addition of the ''animation-trigger-exit-range-start/auto'' keyword.
+The 'timeline-trigger' [=shorthand property=]
+sets all of 'timeline-trigger-name',
+'timeline-trigger-source',
+'timeline-trigger-range',
+and optionally 'timeline-trigger-exit-range'
+at once.
+
+A value of none
+is equivalent to ''none none normal''.
+
+Note: Due to significant potentially ambiguities in the syntax
+('timeline-trigger-name' vs [=timeline=] names in 'timeline-trigger-source';
+[=enter ranges=] vs [=exit ranges=]),
+this shorthand's values must be given in the specified order,
+rather than being settable in any order as is more common.
+
+Issue: I think we need the ''/'' to disambiguate the two ranges?
+
+
+
+
+

+Event Triggers
+
+An event trigger is a [=trigger=]
+which is activated when certain {{Event}}s are fired at the element.
+It is defined on an element with the 'event-trigger' shorthand property,
+or its longhands.
+
+An [=event trigger=] can be defined as either stateless or stateful:
+
+* If stateless, it has a single set of enter events
+    that activate it.
+* If stateful, it has two sets of events, its [=enter events=]
+    and another set of exit events.
+
+[=Event triggers=] are activated when one of its associated {{Event}}s are fired on the page
+with the trigger-defining element as its {{Event/target}}.
+If it's stateful,
+it has a binary trigger state associated with it,
+initially "untriggered":
+while "untriggered", it only activates when the defining element receives one of its [=enter events=],
+performing an associated enter action
+and switching its [=event trigger/trigger state=] to "triggered";
+while "triggered", it only activates when it receives one of its [=exit events=],
+performing an associated exit action
+and switching its [=event trigger/trigger state=] back to "untriggered".
+
+A stateless [=event trigger=] must be given exactly one action for its [=trigger instance=].
+A stateful one can be given one or two:
+the first is its [=event trigger/enter action=],
+and the second, if provided, is its [=event trigger/exit action=];
+if the second is not provided,
+the [=event trigger/exit action=] is to do nothing.
+
+Note: A stateful and stateless [=event trigger=] act differently
+even if you only assign a single action;
+a single-action stateful [=event trigger=] will effectively "turn off"
+until it receives one of its [=exit events=],
+ignoring any of the [=enter events=] after the first,
+while a stateless one will repeatedly trigger for every [=enter event=].
+
+An element can define multiple [=event triggers=],
+using the same {{Event}}s or different ones.
+The set of 'event-trigger' longhands
+form a [=coordinating list property group=],
+with 'event-trigger-name' as the [=coordinating list base property=],
+and each item in the [=coordinated value list=]
+defining the properties of a single [=event trigger=].
+
+Issue: The proposal I drew this text from
+specified that it only cares if the element is the *target* of the event.
+We probably want to allow for bubbling and/or capturing,
+possibly as an opt in/out.
+
+
+

+Naming the Trigger: the 'event-trigger-name' property
+
+
+Name: event-trigger-name
+Value: none | <>#
+Initial: none
+Applies to: all elements
+Inherited: no
+Percentages: N/A
+Computed value: as specified
+Canonical order: per grammar
+Animation type: not animatable
+
 
-The [=exit range=] replaces the [=default range=] once the [=animation trigger=]’s
-[=animation trigger/active interval|active interval=] is entered,
-and redefines the extent of the [=animation trigger=]’s [=animation trigger/active interval|active interval=].
-It is used to extend the [=default range=], for example,
-in cases where exiting the [=animation trigger/active interval|active interval=]
-may create a visual jump that needs to be avoided.
+If ''event-trigger-name/none'' is specified,
+the element does not define any [=event triggers=].
 
-The behavior of 'animation-trigger-exit-range' is further defined in [[web-animations-2#trigger-ranges]].
+If the same <> appears multiple times in the list,
+only the last one defines a [=event trigger=];
+the preceding ones have no effect.
 
-## The 'animation-trigger-exit-range-start' property ## {#animation-trigger-exit-range-start}
+

+Linking an Event: the 'event-trigger-source' property
 
-
-  Name: animation-trigger-exit-range-start
-  Value: [ auto | normal | <> | <> <>? ]#
-  Initial: auto
-  Applies to: all elements
-  Inherited: no
-  Percentages: relative to the specified [=named timeline range=] if one was specified, else to the entire timeline
-  Computed value: list, each item either the keyword ''animation-trigger-exit-range-start/normal'' or a timeline range and progress percentage
-  Animation type: not animatable
+
+Name: event-trigger-source
+Value: [ none | <>+ [ / <>+ ]? ]#
+Initial: none
+Applies to: all elements
+Inherited: no
+Percentages: N/A
+Computed value: as specified
+Animation type: not animatable
 
 
-The 'animation-trigger-exit-range-start' property specifies the start of the [=animation trigger=]’s
-associated [=exit range=].
-
-The values of 'animation-trigger-exit-range-start' have the following meaning:
-
-

-        
auto
-        

-                The start of the trigger’s [=exit range=]
-                is equal to the start of its [=default range=].
-
-        
normal
-        

-                The start of the trigger’s [=exit range=]
-                is the start of its associated [=timeline=];
-                the start of the trigger’s [=animation trigger/active interval|active interval=]
-                is determined as normal.
-
-        
<>
-        

-                The [=exit range=] starts
-                at the specified point on the [=timeline=]
-                measuring from the start of the timeline.
-
-        
<> <>?
-        

-                The [=exit range=] starts
-                at the specified point on the [=timeline=]
-                measuring from the start of the specified [=named timeline range=].
-                If the <> is omitted,
-                it defaults to 0%.
-
+The 'event-trigger-source' property
+specifies what event or events activate the [=event trigger=].
+Its values are:
 
-## The 'animation-trigger-exit-range-end' property ## {#animation-trigger-exit-range-end}
+

+    : none
+    :: The corresponding entry in the [=coordinated value list=] does not define a trigger.
 
-
-  Name: animation-trigger-exit-range-end
-  Value: [ auto | normal | <> | <> <>? ]#
-  Initial: auto
-  Applies to: all elements
-  Inherited: no
-  Percentages: relative to the specified [=named timeline range=] if one was specified, else to the entire timeline
-  Computed value: list, each item either the keyword ''animation-trigger-exit-range-end/normal'' or a timeline range and progress percentage
-  Animation type: not animatable
-
+    : <>+ [ / <>+ ]?
+    :: Defines what event(s) the [=event trigger=] responds to.
+
+        If a ''/'' is used in the value,
+        the [=event trigger=] is stateful;
+        the set of events before the ''/'' are the [=event trigger's=] [=enter events=],
+        while those after the ''/'' are the [=exit events=].
+        (The same events can occur in both sets.)
 
-The 'animation-trigger-exit-range-end' property specifies the end of the [=animation trigger=]’s
-associated [=exit range=].
-
-The values of 'animation-trigger-exit-range-start' have the following meaning:
-
-

-        
auto
-        

-                The end of the trigger’s [=exit range=]
-                is equal to the end of its [=default range=].
-
-        
normal
-                

-                        The end of the trigger’s [=exit range=]
-                        is the end of its associated [=timeline=];
-                        the end of the trigger’s [=animation trigger/active interval|active interval=]
-                        is determined as normal.
-
-                
<>
-                

-                        The [=exit range=] ends
-                        at the specified point on the [=timeline=]
-                        measuring from the start of the timeline.
-
-                
<> <>?
-                

-                        The [=exit range=] ends
-                        at the specified point on the [=timeline=]
-                        measuring from the start of the specified [=named timeline range=].
-                        If the <> is omitted,
-                        it defaults to 100%.
+        Otherwise,
+        the [=event trigger=] is stateless,
+        and the provided events are its [=enter events=].
 
 
-## The 'animation-trigger' property ## {#animation-trigger}
+
+<> = activate | click | touch | dblclick | keypress(<>) | ...
+
+
+Issue: Figure out the full set of events we want to handle.
 
-The 'animation-trigger' property is a [=shorthand property|shorthand=]
-that sets 'animation-trigger-behavior', 'animation-trigger-timeline',
-'animation-trigger-range-start', 'animation-trigger-range-end',
-'animation-trigger-exit-range-start', and 'animation-trigger-exit-range-end'
-together in a single declaration,
-specifying the [=animation trigger=] for an animation.
+
+

+The 'event-trigger' Shorthand
 
 
-Name: animation-trigger
-Value: <>#
-Initial: see individual properties
+Name: event-trigger
+Value: none | [ <<'event-trigger-name'>> <<'event-trigger-source'>> ]#
+Initial: none
 Applies to: all elements
 Inherited: no
 Percentages: N/A
-Computed value: see individual properties
-Canonical order: per grammar
-Animation Type: not animatable
+Computed value: as specified
+Animation type: not animatable
 
 
-
-<single-animation-trigger> = <> || [ none | auto | [ [ <> | <> | <> ] [ normal | <> | <> <>? ]{0,4} ] ]
-
+The 'event-trigger' [=shorthand property=]
+sets both 'event-trigger-name' and 'event-trigger-source' at once.
+
+A value of none
+is equivalent to ''none none''.
+
+
+
 
 # Animation Events # {#events}
 
diff --git a/css-backgrounds-3/Overview.bs b/css-backgrounds-3/Overview.bs
index 10cee759b0a4..ffea8cf1e5a9 100644
--- a/css-backgrounds-3/Overview.bs
+++ b/css-backgrounds-3/Overview.bs
@@ -36,6 +36,10 @@ spec:css-color-4; type:value; text:transparent
 spec:selectors-3; type:selector; text: ::first-letter
 spec:selectors-3; type:selector; text: ::first-line
 spec:css-values-3; type:type; text:
+spec:html; type:element; text:body
+spec:css-sizing-3; type:dfn; text:size
+spec:css-sizing-3; type:dfn; text:width
+spec:css-sizing-3; type:dfn; text:height
 
 
 
Introduction
@@ -947,8 +951,28 @@ Painting Area: the 'background-clip' property
 		background-clip-color.html
 		background-clip-content-box-001.html
 		background-clip-content-box-002.html
+		background-clip-content-box-with-border-radius-002.html
+		background-clip-content-box-with-border-radius-003.html
+		background-clip-padding-box-with-border-radius-002.html
+		background-clip-padding-box-with-border-radius-003.html
 		background-clip-padding-box-001.html
 		background-clip-padding-box-with-border-radius.html
+		background-clip/clip-border-area-background-geometry.html
+		background-clip/clip-border-area-border-image.html
+		background-clip/clip-border-area-border-on-top.html
+		background-clip/clip-border-area-box-decoration-break.html
+		background-clip/clip-border-area-multiple-backgrounds.html
+		background-clip/clip-border-area-on-body-not-propagated-to-root.html
+		background-clip/clip-border-area-on-body-propagated-to-root.html
+		background-clip/clip-border-area-on-root.html
+		background-clip/clip-border-area.html
+		background-clip/clip-text-ellipsis.html
+		background-clip/clip-text-on-body-not-propagated-to-root.html
+		background-clip/clip-text-on-body-propagated-to-root.html
+		background-clip/clip-text-on-root.html
+		background-clip/clip-text-out-of-flow-child.html
+		background-clip/clip-text-text-decorations.html
+		background-clip/clip-text-text-emphasis.html
 		background-clip/clip-rounded-corner.html
 		background-clip/clip-text-animated-text.html
 		background-clip/clip-text-dynamic-2.html
@@ -1565,6 +1589,13 @@ Positioning Area: the 'background-origin' property
 	with other comma-separated background properties
 	to form each [=background image layer=].
 
+

+Serialization of 'background-size' values
+
+	The [=specified value=] and [=computed value=] of the <> type
+	always serialize as two values, even when the second value is ''background-size/auto'',
+	due to the [[cssom#serializing-css-values|shortest, most backwards-compatible serialization principle]].
+
 

 Backgrounds Shorthand: the 'background' property
 
@@ -2453,13 +2484,37 @@ Corner Shaping
 
 	The [=margin edge=], being outside the [=border edge=],
 	calculates its radius by adding the corresponding margin thickness
-	to each border radius.
-	However, in order to create a sharper corner when the border radius is small
-	(and thus ensure continuity between round and sharp corners),
-	when the [=border radius=] is less than the margin,
-	the margin is multiplied by the proportion 1 + (r-1)3,
-	where r is the ratio of the border radius to the margin,
-	in calculating the corner radii of the margin box shape.
+	to each border radius, with the corresponding [=outset-adjusted border radius=] applied.
+
+	
+		background-clip-content-box-with-border-radius-002.html
+		background-clip-content-box-with-border-radius-003.html
+		background-clip-padding-box-with-border-radius-002.html
+		background-clip-padding-box-with-border-radius-003.html
+	
+
+

+
+	When expanding an [=edge=] that has a [=border radius=], e.g. for computing the [=margin edge=], 'box-shadow' spread, or 'overflow-clip-margin',
+	the different [=border radius=] values are adjusted so that a small rounded corner with a big outset does not appear to be disproportionally round.
+
+	This is done by computing the corresponding [=outset-adjusted border radius=].
+
+	To compute the outset-adjusted border radius given the 2-dimensional [=size=]s |edge|, |radius|, and |outset|:
+		1. Let |coverage| be 2 * min(|radius|'s [=width=] / |edge|'s [=width=], |radius|'s [=height=] / |edge|'s [=height=]).
+		1. Let |adustedRadiusWidth| be the [=adjusted radius dimension=] given |coverage|, |radius|'s [=width=], and |outset|'s [=width=].
+		1. Let |adustedRadiusHeight| be the [=adjusted radius dimension=] given |coverage|, |radius|'s [=height=], and |outset|'s [=height=].
+		1. Return (|adustedRadiusWidth|, |adustedRadiusHeight|).
+
+	To compute the adjusted radius dimension given numbers |coverage|, |radius|, and |outset|:
+		1. If |radius| is greater than |spread|, or if |coverage| is greater than 1, then return |radius| + |outset|.
+		1. Let |ratio| be |radius| / |outset|.
+		1. Return |radius| + |outset| * (1 - (1 - |ratio|)3 * (1 - |coverage|3)).
+
+		Note: this algorithm is designed to reduce the effect of the |outset| (or spread) on the shape of the corner.
+		The |coverage| factor makes this reduction more pronounced for rectangular shapes (where the [=border-radius=] is close to 0),
+		and less pronounced for elliptical shapes (where the [=border-radius=] is close to 50%).
+
 
 
 

@@ -2741,6 +2796,11 @@ Border Images
 		
 	
 
+	
+		border-image-021.html
+		border-image-outset-004.html
+	
+
 

 Image Source: the 'border-image-source' property
 
@@ -3342,7 +3402,7 @@ Border Image Shorthand: the 'border-image' property
 	represented by 2-4 length values, an optional color, and an optional ''box-shadow/inset'' keyword.
 	Omitted lengths are 0; omitted colors default to ''currentColor''.
 	
-	<> = <>? && [<>{2} <>? <>?] && inset?
+	<> = <>? && [ <>{2} [ <> <>? ]? ] && inset?
 
 	The components of each <> are interpreted as follows:
 
@@ -3544,22 +3604,15 @@ Shadow Shape, Spread, and Knockout
 	the corner radii of the shadow are also increased (decreased, for inner shadows)
 	from the border-box (padding-box) radii by adding (subtracting)
 	the [=spread distance=] (and flooring at zero).
-	However, in order to create a sharper corner when the border radius is small
-	(and thus ensure continuity between round and sharp corners),
-	when the [=border radius=] is less than the [=spread distance=]
-	(or in the case of an inner shadow,
-	less than the absolute value of a negative [=spread distance=]),
-	the [=spread distance=]
-	is first multiplied by the proportion 1 + (r-1)3,
-	where r is the ratio of the border radius to the [=spread distance=],
-	in calculating the corner radii of the spread shadow shape.
-	For example, if the border radius is 10px and the [=spread distance=] is 20px (r = .5),
-	the corner radius of the shadow shape will be 10px + 20px × (1 + (.5 - 1)3) = 27.5px
-	rather than 30px.
-	This adjustment is applied independently to the radii in each dimension.
+	For outer shadows, the [=border-radius=] is then [=outset-adjusted border radius|adjusted=], independently in each dimension,
+	to preserve the sharpness of rounded corners.
 
 	The 'border-image' does not affect the shape of the box-shadow.
 
+	
+		box-shadow-radius-generated.html
+	
+
 

 Blurring Shadow Edges
 
@@ -3657,6 +3710,22 @@ Level 3
 

 Changes
 
+

+Changes since the 11 March 2024 Candidate Recommendation Draft
+
+	

+		
+		
Altered the border-radius outset adjustment,
+			so the radius reduction factor in the
+			minimum radius percentage of the corner, makes it less pronounced
+			the closer the corner's border-radius gets to 50%.
+			(Issue 7103)
+		
+		
Fixed syntax of 'box-shadow' to avoid allowing negative blur radii,
+			aligning it with the prose.
+		
Cross linked to 'ink overflow' terminology
+	
+
 

 Changes since the 14 February 2023 Candidate Recommendation Snapshot
 
@@ -3681,6 +3750,8 @@ Changes since the 14 February 2023 Candidate Recommendation Snapshot
 			[=CSS/value definition syntax=].
 		
Fixed the definition for where box shadows apply.
 			(Issue 9286)
+		
Defined serialization of 'background-size' in [[#bg-size-serialization]].
+			(Issue 7802)
 	
 
 
@@ -4132,4 +4203,7 @@ Changes Since the 17 December 2009 Candidate Recommendation
 	color-mix-currentcolor-outline-repaint-parent.html
 	color-mix-currentcolor-outline-repaint.html
 	first-letter-space-not-selected.html
-
\ No newline at end of file
+	animations/background-color-animation-custom-property.html
+	animations/background-color-animation-custom-timing-function-reverse.html
+	animations/background-color-animation-custom-timing-function.html
+
diff --git a/css-backgrounds-3/radius-expansion.html b/css-backgrounds-3/radius-expansion.html
index ff5cfb0d7eab..3519c93d7ba4 100644
--- a/css-backgrounds-3/radius-expansion.html
+++ b/css-backgrounds-3/radius-expansion.html
@@ -78,6 +78,14 @@
 		
 		Oriol's variant of current spec (adding a linear factor)
 	
+	
+		
+		Noam's old/new spectrum
+	
+	
+		
+		Noam's old/new spectrum, preserving circular corners
+	
 
 

 
 
-

+

 {{preferences}} attribute
 
 When getting the {{preferences}} attribute always return the same instance of the {{PreferenceManager}} object.
@@ -3218,15 +3369,15 @@ When getting the {{preferences}} attribute always return the same instance of th
 
 
-

+

 {{colorScheme}} attribute
 
 The {{colorScheme}} attribute is a {{PreferenceObject}} used to override the user's preference for the color scheme of the site.
@@ -3248,7 +3399,7 @@ If an override is set for this preference:
 - The user agent MUST also use this override when sending [[USER-PREFERENCE-MEDIA-FEATURES-HEADERS#sec-ch-prefers-color-scheme]].
 - The user agent MUST also use this override for any UA features that are normally affected by [[#prefers-color-scheme]].
 
-

+

 {{contrast}} attribute
 
 The {{contrast}} attribute is a {{PreferenceObject}} used to override the user's preference for the contrast of the site.
@@ -3272,7 +3423,7 @@ If an override is set for this preference:
 
 Note: Unlike the media feature this preference is NOT able to be set to ''@media/prefers-contrast/custom'' as this is tightly coupled to the [[#forced-colors]].
 
-

+

 {{reducedMotion}} attribute
 
 The {{reducedMotion}} attribute is a {{PreferenceObject}} used to override the user's preference for reduced motion on the site.
@@ -3295,7 +3446,7 @@ If an override is set for this preference:
 
 Note: An example of a UA feature that is affected by this preference could be disabling smooth scrolling, or pausing marquee elements.
 
-

+

 {{reducedTransparency}} attribute
 
 The {{reducedTransparency}} attribute is a {{PreferenceObject}} used to override the user's preference for reduced transparency on the site.
@@ -3316,7 +3467,7 @@ If an override is set for this preference:
 - The user agent MUST also use this override when sending [[USER-PREFERENCE-MEDIA-FEATURES-HEADERS#sec-ch-prefers-reduced-transparency]].
 - The user agent MUST also use this override for any UA features that are normally affected by [[#prefers-reduced-transparency]].
 
-

+

 {{reducedData}} attribute
 
 The {{reducedData}} attribute is a {{PreferenceObject}} used to override the user's preference for reduced data usage on the site.
@@ -3338,24 +3489,24 @@ If an override is set for this preference:
 - The user agent MUST also use this override when calculating the [[SAVEDATA#savedata-attribute]].
 - The user agent MUST also use this override for any UA features that are normally affected by [[#prefers-reduced-data]].
 
-

+

 {{PreferenceObject}} interface
 
 
 
-

+

 {{override}} attribute
 
 

@@ -3367,7 +3518,7 @@ interface PreferenceObject : EventTarget {
 	1. Return |override|.
 
 
-

+

 {{PreferenceObject/value}} attribute
 
 

@@ -3380,7 +3531,7 @@ interface PreferenceObject : EventTarget {
 	1. Return |value|.
 
 
-

+

 {{validValues}} attribute
 
 

@@ -3402,9 +3553,10 @@ interface PreferenceObject : EventTarget {
 				 
"{{reducedData}}"
 				 
Return the result of [=get valid values for reducedData=].
 			 
+		
 
 
-

+

 {{onchange}} event handler attribute
 
 The onchange attribute is an [=event handler IDL attribute=] for
@@ -3422,7 +3574,7 @@ update steps:
 	1. If |document| is null or |document| is not [=Document/fully active=], terminate this algorithm.
 1. Fire an event named change at |preference|.
 
-

+

 {{requestOverride()}} method
 
 

@@ -3471,7 +3623,7 @@ Issue: Is TypeError correct here?
 
 Note: The `change` event is fired when the computed value changes, but when a new override is set it is also fired if the value hasn't changed.
 
-

+

 {{clearOverride()}} method
 
 

@@ -3482,7 +3634,7 @@ Note: The `change` event is fired when the computed value changes, but when a ne
 	1. If an override for |preference| exists, set |override| to the value of that override.
 	1. If |override| is null, then return.
 	1. Clear the override for |preference|.
-	1. Let |newValue| be the preference object's |value|.
+	1. Let |newValue| be the preference object's value.
 	1. If |newValue| is equal to |override|, then:
 	1. Fire an event named change at [=this=].
 
@@ -3565,8 +3717,8 @@ Appendix A: Deprecated Media Features
 
 	
To query for the size of the viewport (or the page box
 	on page media), the '@media/width', '@media/height' and aspect-ratio media features
-	should be used, rather than 'device-width', 'device-height' and
-	'device-aspect-ratio', which refer to the physical size of the device
+	should be used, rather than '@media/device-width', '@media/device-height' and
+	'@media/device-aspect-ratio', which refer to the physical size of the device
 	regardless of how much space is available for the document being laid out. The
 	device-* media features are also sometimes used as a proxy to detect
 	mobile devices. Instead, authors should use media features that better
@@ -3582,7 +3734,7 @@ device-width
 	Type: range
 	
 
-	The 'device-width' media feature describes the width of the rendering surface of the output device.
+	The '@media/device-width' media feature describes the width of the rendering surface of the output device.
 	For [=continuous media=], this is the width of the Web-exposed screen area.
 	For [=paged media=], this is the width of the page sheet size.
 
@@ -3611,7 +3763,7 @@ device-height
 	Type: range
 	

-Appendix B: Privacy Considerations

- Appendix C: Security Considerations

Changes

video-height, and video-resolution. (See Issue 5044) - * Renamed 'prefers-contrast' values high and low + * Renamed '@media/prefers-contrast' values high and low to ''prefers-contrast/more'' and ''prefers-contrast'' less. (See Issue 2943) - * Rework the interaction between 'prefers-contrast' and 'forced-colors', + * Rework the interaction between '@media/prefers-contrast' and '@media/forced-colors', retiring prefers-contrast: forced and introducing ''prefers-contrast/custom''. (See Issue 5433) and Issue 6036) - * Added the 'horizontal-viewport-segments' and 'vertical-viewport-segments' media feature. + * Added the '@media/horizontal-viewport-segments' and '@media/vertical-viewport-segments' media feature. (See Issue 6234) - * Added the 'nav-controls' media feature. + * Added the '@media/nav-controls' media feature. (See Issue 6234) - * Make it possible for multiple values of 'dynamic-range' to match at the same time. + * Make it possible for multiple values of '@media/dynamic-range' to match at the same time. (See Issue 6793) @@ -3787,7 +3873,7 @@ The following additions were made to this module since the

• - Added a UA style sheet rule for 'inverted-colors'. + Added a UA style sheet rule for '@media/inverted-colors'.
• Added the ''prefers-contrast: forced'' value. @@ -3824,7 +3910,7 @@ The following additions were made to this module since the
  • - Added 'video-*' and 'dynamic-range' media features + Added 'video-*' and '@media/dynamic-range' media features
  • Removed 'prefers-color-scheme: no-preference' @@ -3849,19 +3935,17 @@ The following additions were made to create the First Public Working Draft of th
    • - Reinstate the light-level, 'inverted-colors', and Custom Media Queries sections + Reinstate the light-level, '@media/inverted-colors', and Custom Media Queries sections from earlier Media Queries Level 4 drafts.
    • - Added 'prefers-reduced-motion', - 'prefers-reduced-transparency', - 'prefers-contrast', - 'prefers-color-scheme', - and 'forced-colors' media features. + Added '@media/prefers-reduced-motion', + '@media/prefers-reduced-transparency', + '@media/prefers-contrast', + '@media/prefers-color-scheme', + and '@media/forced-colors' media features.
    - -

    Acknowledgments

    @@ -3871,61 +3955,124 @@ This specification is the product of the W3C Working Group on Cascading Style Sheets. Comments from - Adam Argyle, - Amelia Bellamy-Royds, - Andreas Lind, - Andres Galante, - Arve Bersvendsen, - Björn Höhrmann, - Chen Hui Jing, - Chris Lilley, - Chris Rebert, - Christian Biesinger, - Christoph Päper, - Elika J. Etemad (fantasai), - Emilio Cobos Álvarez, - François Remy, - Frédéric Wang, - Fuqiao Xue, - Greg Whitworth, - Ian Pouncey, - James Craig, - Jay Harris, - Jinfeng Ma, - Kivi Shapiro, - L. David Baron, - Masataka Yakura, - Matt Giuca, - Melinda Grant, - Michael Smith, - Nicholas C. Zakas - Patrick H. Lauke, - Philipp Hoschka, - Rick Byers, - Rijk van Geijtenbeek, - Rik Cabanier, - Roger Gimson, - Rossen Atanassov, - Sam Sneddon, - Sigurd Lerstad, - Simon Kissane, - Simon Pieters, - Stephen Chenney, - Steven Pemberton, - Susan Lesch, - Tantek Çelik, - Thomas Wisniewski, - Vi Nguyen, - Xidorn Quan, - Yves Lafon, - akklesed, - and 張俊芝 +Adam Argyle, +Amelia Bellamy-Royds, +Andreas Lind, +Andres Galante, +Arve Bersvendsen, +Björn Höhrmann, +Chen Hui Jing, +Chris Lilley, +Chris Rebert, +Christian Biesinger, +Christoph Päper, +Elika J. Etemad (fantasai), +Emilio Cobos Álvarez, +François Remy, +Frédéric Wang, +Fuqiao Xue, +Greg Whitworth, +Ian Pouncey, +James Craig, +Jay Harris, +Jinfeng Ma, +Kivi Shapiro, +L. David Baron, +Masataka Yakura, +Matt Giuca, +Melinda Grant, +Michael Smith, +Nicholas C. Zakas +Patrick H. Lauke, +Philipp Hoschka, +Rick Byers, +Rijk van Geijtenbeek, +Rik Cabanier, +Roger Gimson, +Rossen Atanassov, +Sam Sneddon, +Sigurd Lerstad, +Simon Kissane, +Simon Pieters, +Stephen Chenney, +Steven Pemberton, +Susan Lesch, +Tantek Çelik, +Thomas Wisniewski, +Vi Nguyen, +Xidorn Quan, +Yves Lafon, +akklesed, +and 張俊芝 improved this specification.

    Privacy Considerations

    -No new privacy considerations have been reported on this specification. + This section is not normative. + +
    + + Issue: this section is incomplete + + Many media features enable fingerprinting of users + based on the display and interaction characteristics of their device: + + * Colors: '@media/color', '@media/color-index', '@media/monochrome', '@media/color-gamut' and '@media/dynamic-range' + * Viewport characteristics: '@media/aspect-ratio', '@media/orientation', + '@media/horizontal-viewport-segments' and + '@media/vertical-viewport-segments' + * Display quality: '@media/resolution', '@media/scan', '@media/grid', '@media/update' and '@media/environment-blending' + * Interaction devices: '@media/pointer', '@media/hover', '@media/any-pointer' and '@media/any-hover'. + + The '@media/environment-blending' feature is of particular concern + because it suggests where a user may be located, + and is likely present in a small set of devices. + Uncommon device properties are stronger fingerprinting features + because they help segment devices into smaller sets. + + Media features that reflect operating system preferences are a fingerprinting risk + because such preferences are correlated with characteristics of the user themselves: + + * The '@media/prefers-reduced-data' media feature may be correlated with low income and limited data. + * The '@media/prefers-reduced-motion', '@media/prefers-color-scheme', '@media/prefers-reduced-transparency', + '@media/forced-colors' and '@media/inverted-colors' queries reflect affordances for a range of special needs. + + Properties dependent on one of the above media queries may be accessed by script: + + * Colors and other property values may be directly accessed through computed style, + though user agents may elect to return constants for some colors + (see, for example, CSS Color 4). + * Layout affecting properties (such as font size) influence lengths, positions and sizes available to script. + + User agents may disable these media features when users have expressed sensitivity to tracking. + Alternatively, user agents may limit the combination of features within a single page + to reduce the fingerprinting power of the page. + + The {{PreferenceManager}} object allows querying some user-preference [=media features=]. This + is not a privacy leak, as that information is already trivially + available by using [=media features=] themselves. + + The {{PreferenceManager}} object also allows overriding these user-preference [=media features=]; this + is also neither a privacy nor accessibility regression, as the [=media features=] were already ignorable by simply + not querying them. + +

    Security Considerations

    -No new security considerations have been reported on this specification. + This section is not normative. + +
    + + Issue: this section is incomplete + + The '@media/display-mode' media feature allows an origin + access to aspects of a user’s local computing environment and, + particularly when used together with an [=application manifest=] [=manifest/display=] member [[APPMANIFEST]], + allows an origin some measure of control over a user agent’s native UI. + Through a CSS media query, a script can know the display mode of a web application. + An attacker could, in such a case, + exploit the fact that an application is being displayed in fullscreen + to mimic the user interface of another application. + +
    diff --git a/resize-observer-1/Overview.bs b/resize-observer-1/Overview.bs index a1b146f06ea0..5566e51c535d 100644 --- a/resize-observer-1/Overview.bs +++ b/resize-observer-1/Overview.bs @@ -1,5 +1,5 @@

    -Title: Resize Observer
    +Title: Resize Observer Module Level 1
     Shortname: resize-observer
     Level: 1
     Status: ED
    diff --git a/scroll-animations-1/Overview.bs b/scroll-animations-1/Overview.bs
    index ec3643632e53..7ce2f0c22af1 100644
    --- a/scroll-animations-1/Overview.bs
    +++ b/scroll-animations-1/Overview.bs
    @@ -5,7 +5,7 @@
     	}
     
     
    -Title: Scroll-driven Animations
    +Title: Scroll-driven Animations Module Level 1
     Group: CSSWG
     Status: ED
     Work Status: revising
    diff --git a/selectors-4/Overview.bs b/selectors-4/Overview.bs
    index 14d3565a495b..02d714508d38 100644
    --- a/selectors-4/Overview.bs
    +++ b/selectors-4/Overview.bs
    @@ -29,6 +29,8 @@ At Risk: the '':blank'' pseudo-class
     Ignored Terms: function token, Document, DocumentFragment, math, h1, shadow tree, querySelector(), quirks mode, button, a, span, object, p, div, q, area, link, label, input, html, em, li, ol, pre, CSS Value Definition Syntax
     Ignored Vars: identifier, i
     Ignore MDN Failure: #the-target-within-pseudo
    +WPT Path Prefix: css/selectors/
    +WPT Display: closed
     
     
     spec:css-values-4; type:dfn; text:identifier
    @@ -58,6 +60,8 @@ Introduction

Module Interactions

Selector Syntax and Structure

Featureless Elements

custom-element:defined { visibility: visible }

p[title*="hello"] 

div p *[href]

@@ -3863,6 +4831,7 @@ Grammar
 		be written with only a single ":" character at their front,
 		making them resemble a <>.
 
+
 

 <> and <>
 
@@ -3929,6 +4898,7 @@ API Hooks
 	and details like the exact order of elements returned from querySelector
 	seem to make more sense being defined in the DOM specification than in Selectors.
 
+
 

 Parse A Selector
 
@@ -3953,6 +4923,7 @@ Parse A Selector
 			return selector.
 	
 
+
 

 Parse A Relative Selector
 
@@ -3977,6 +4948,7 @@ Parse A Relative Selector
 			return selector.
 	
 
+
 

 Match a Selector Against an Element
 
@@ -4021,6 +4993,7 @@ Match a Selector Against an Element
 		Otherwise, return failure.
 	
 
+
 

 Match a Selector Against a Pseudo-element
 
@@ -4052,6 +5025,7 @@ Match a Selector Against a Pseudo-element
 	(that is, if this doesn't happen for any of the complex selectors in selector),
 	return failure.
 
+
 

 Match a Selector Against a Tree
 
@@ -4123,6 +5097,7 @@ Match a Selector Against a Tree
 
 	
 
+
 

 Appendix A: Guidance on Mapping Source Documents & Data to an Element Tree
 
@@ -4230,6 +5205,10 @@ Appendix A: Guidance on Mapping Source Documents & Data to an Element Tree
 Appendix B: Obsolete but Required -webkit- Parsing Quirks for Web Compat
 
+	
+		webkit-pseudo-element.html
+	
+
 	This appendix is normative.
 
 	Due to legacy Web-compat constraints,
@@ -4303,6 +5282,7 @@ Appendix B: Obsolete but Required -webkit- Parsing Quirks for Web C
 			and all right-thinking web developers.
 		
 
+
 

 Appendix C: Example Privacy-Preserving '':visited'' Restrictions
 
@@ -4404,29 +5384,36 @@ while still preserving as much of the usefulness of '':visited'' as pos
 
 
 
-
 

 Changes
 
+

+Changes since the 11 November 2022 Working Draft
+
+	Significant changes since the 11 November 2022 Working Draft:
+
+	* Marked '':blank'' as at-risk and removed the at-risk status from '':read-write'' and '':has()''
+	* Added '':popover-open'' pseudo-class.
+		(Issue 8637)
+	* Made '':has()'' and the selector argument of '':nth-child()''/'':nth-last-child()''
+		no longer forgiving.
+		(Issue 7676)
+	* Moved the legacy single-colon pseudo-element syntax into the grammar itself.
+		(Issue 8122)
+
 

 Changes since the 7 May 2022 Working Draft
 
 	Significant changes since the 7 May 2022 Working Draft:
 
-	* Marked '':blank'' as at-risk and removed the at-risk status from '':read-write'' and '':has()''
 	* Added '':open'' pseudo-class.
 		(Issue 7319,
 		Issue 11039)
-	* Added '':popover-open'' pseudo-class.
-		(Issue 8637)
 	* Disallowed [=pseudo-elements=] from '':has()'' unless explicitly allowed
 		by the pseudo-element’s definition.
 		(Issue 7463)
 	* Disallowed nesting of '':has()''.
 		(Issue 7344)
-	* Made '':has()'' and the selector argument of '':nth-child()''/'':nth-last-child()''
-		no longer forgiving.
-		(Issue 7676)
 	* Defined matching of ''::lang("")'' and of elements not tagged with a language.
 		(Issue 6915)
 	* Untangled the concepts of "scoped" and "relative" selectors completely.
@@ -4438,8 +5425,7 @@ Changes since the 7 May 2022 Working Draft
 		(Issue 3760)
 	* Defined '':-webkit-autofill'' [=legacy selector alias=].
 		(Issue 7474)
-	* Moved the legacy single-colon pseudo-element syntax into the grammar itself.
-		(Issue 8122)
+
 
 

 Changes since the 21 November 2018 Working Draft
@@ -4477,6 +5463,7 @@ Changes since the 21 November 2018 Working Draft
 			when a <> token is missing.
 	
 
+
 

 Changes since the 2 February 2018 Working Draft
 
@@ -4505,6 +5492,7 @@ Changes since the 2 February 2018 Working Draft
 		(See [[#grammar]].)
 	
 
+
 

 Changes since the 2 May 2013 Working Draft
 
@@ -4556,6 +5544,7 @@ Changes since the 2 May 2013 Working Draft
 	Note: The 1 February 2018 draft included an inadvertent commit of unfinished work;
 	2 February 2018 has reverted this commit (and fixed some links because why not).
 
+
 

 Changes since the 23 August 2012 Working Draft
 
@@ -4572,6 +5561,7 @@ Changes since the 23 August 2012 Working Draft
 		
The '':local-link()'' pseudo-class now ignores trailing slashes.
 	
 
+
 

 Changes since the 29 September 2011 Working Draft
 
@@ -4585,6 +5575,7 @@ Changes since the 29 September 2011 Working Draft
 		
Changed column combinator from double slash to double pipe.
 	
 
+
 

 Changes Since Level 3
 
@@ -4606,6 +5597,7 @@ Changes Since Level 3
 		
Added case-insensitive / case-sensitive attribute-value matching flags.
 	
 
+
 

 Acknowledgements
 
@@ -4625,7 +5617,7 @@ Acknowledgements
 	Lea Verou
 
 
-	
Privacy Considerations
+
Privacy Considerations
 
 	

 		

@@ -4642,5 +5634,26 @@ Acknowledgements
 	The Privacy Considerations
 	could also be considered to affect Security.
 
-
-
+
+
+
\ No newline at end of file
diff --git a/selectors-5/Overview.bs b/selectors-5/Overview.bs
index 117df878b07a..036ed686b075 100644
--- a/selectors-5/Overview.bs
+++ b/selectors-5/Overview.bs
@@ -4,6 +4,7 @@ Group: CSSWG
 Shortname: selectors
 Level: 5
 Status: ED
+!Delta Spec: yes
 Work Status: Exploring
 ED: https://drafts.csswg.org/selectors-5/
 TR: https://www.w3.org/TR/selectors-5/
@@ -11,6 +12,8 @@ Editor: Elika J. Etemad / fantasai, Apple, http://fantasai.inkedblade.net/contac
 Editor: Tab Atkins Jr., Google, http://xanthir.com/contact/, w3cid 42199
 Abstract: Selectors are patterns that match against elements in a tree, and as such form one of several technologies that can be used to select nodes in a document. Selectors have been optimized for use with HTML and XML, and are designed to be usable in performance-critical code. They are a core component of CSS (Cascading Style Sheets), which uses Selectors to bind style properties to elements in the document.
 Abstract: Selectors Level 5 describes the selectors that already exist in [[!selectors-4]], and further introduces new selectors for CSS and other languages that may need them.
+WPT Path Prefix: css/selectors/
+WPT Display: closed
 

@@ -141,6 +144,10 @@ Exposing custom state: the '':state()'' pseudo-class
 	whose [=states set=] contains a string
 	that [=string/is=] the selector's argument's value.
 
+	
+		parsing/parse-state.html
+	
+
 	
 
@@ -173,13 +180,16 @@ Heading Structures: the heading pseudo-classes '':heading'', and '':heading()''<
 
 	As a functional pseudo-class,
 	:heading()
-	notation represents elements that have a heading level among An+B.
+	notation represents elements that have a heading level among matching
+	any of the provided integer values.
 	The syntax is:
 
 	
-		:heading() = :heading( <># )
+		:heading() = :heading( <># )
 	
 
+	where <level> is a <> with its type flag set to "integer".
+
 	The [=specificity=] of '':heading()'' is that of a class.
 
 	

@@ -188,16 +198,21 @@ Heading Structures: the heading pseudo-classes '':heading'', and '':heading()''<
 		500, additionally heading levels 1 and 2 will be underlined, while 3 and
 		beyond will have no text-decoration:
 
-		
:heading(-n+3) { font-weight: 900; }
-		
:heading(n+6) { font-weight: 500; }
+		
:heading(1, 2, 3) { font-weight: 900; }
+		
:heading(6, 7, 8, 9) { font-weight: 500; }
 		
:heading(1, 2) { text-decoration: underline; }
-		
:heading(n+3) { text-decoration: none; }
+		
:heading(3, 4, 5, 6, 7, 8, 9) { text-decoration: none; }
 	
 
 	Note: The heading level might be different from an element's
 	type selector. Thus, a selector ''h1:heading(3)'' matches any
 	''h1'' tag which has an exposed heading level of 3.
 
+	
+		heading.html
+		parsing/parse-heading.html
+	
+
 

 Combinators
 
diff --git a/web-animations-1/Overview.bs b/web-animations-1/Overview.bs
index f0992e335134..465dcb821445 100644
--- a/web-animations-1/Overview.bs
+++ b/web-animations-1/Overview.bs
@@ -56,7 +56,7 @@ div.informative-bg h4 {
 
 
 
-Title: Web Animations
+Title: Web Animations Module Level 1
 Group: CSSWG
 Shortname: web-animations
 Status: ED
diff --git a/web-animations-2/Overview.bs b/web-animations-2/Overview.bs
index 7e244743076c..66dca58ae19a 100644
--- a/web-animations-2/Overview.bs
+++ b/web-animations-2/Overview.bs
@@ -57,15 +57,15 @@ dl.switch > dt > ul > li {
 
 
 
-Title: Web Animations Level 2
+Title: Web Animations Module Level 2
 Status: ED
-Warning: not ready
 Work Status: Exploring
 Shortname: web-animations
 ED: https://drafts.csswg.org/web-animations-2/
 TR: https://www.w3.org/TR/web-animations-2/
 Version history: https://github.com/w3c/csswg-drafts/commits/main/web-animations-2
 Level: 2
+!Delta Spec: yes
 
 Group: csswg
 !Participate: Fix the text through GitHub
@@ -86,6 +86,7 @@ Abstract: This specification defines a model for synchronization and
     features.
 Ignored Vars: auto-rewind, current direction, index, initial progress,
     timeline, new timeline, t, going forwards, did trigger
+WPT Path Prefix: web-animations
 
 
 urlPrefix: https://drafts.csswg.org/web-animations-1/; type: dfn; spec: web-animations-1
@@ -156,23 +157,6 @@ only the differences from Web Animations Level 1 [[!WEB-ANIMATIONS-1]].
 Once the Level 1 specification is closer to complete, it will be merged
 with the additions here into a complete level 2 specification.

 
-
Changes since level 1
-
-This specification introduces the following changes compared to the
-previous level of this specification:
-
-*   group effects and sequence effects,
-*   an animation effect-specific
-    [=animation effect/playback rate=],
-*   Support for non-monotonic (scroll) timelines.
-
-

-This module also includes some exploratory proposals for [[#custom-effects]],
-however there are some concerns about the design of this feature
-and it may be replaced in a future revision.
-See discussion.
-
-
 
Timing model
 
 This section describes and defines the behavior of the Web Animations
@@ -3804,6 +3788,46 @@ Add:
 >
 >     Note: Need to spec this properly somewhere.
 
+
+
+
Changes
+
+
Changes since level 1
+
+This specification introduces the following changes compared to the
+previous level of this specification:
+
+*   group effects and sequence effects,
+*   an animation effect-specific
+    [=animation effect/playback rate=],
+*   Support for non-monotonic (scroll) timelines.
+
+

+This module also includes some exploratory proposals for [[#custom-effects]],
+however there are some concerns about the design of this feature
+and it may be replaced in a future revision.
+See discussion.
+
+
+

+Changes since the First Public Working Draft of 21 February 2023
+
+
+

+    
+    
Renamed animation-trigger-type to animation-trigger-behavior
+    
Corrected mention of start time to current time
+    
Corrected syntax of rangeStart, rangeEnd, exitRangeStart and exitRangeEnd attributes on AnimationTrigger interface (Issue 11624)
+    
Specified the animation-trigger property, added the AnimationTrigger interface 
+    
Changed progress to overallProgress (Issue 8799)
+    
Specified Animation progress API (Issue 9937)
+    
Clarified that start time of the animation is auto-aligned with the animation range boundary when it has not been explicitly set (Issue 9181)
+    
Fixed IDL definition of KeyframeAnimationOptions
+    
Expanded offset syntax for keyframes (Issue 7637)
+    
Added rangeStart/rangeEnd to Animatable interface (Issue 7589)
+    
Tidied up effect stack definitions (Issue 8497)
+
+
 Privacy Considerations {#priv}
 ===============================================