@@ -1341,80 +1341,6 @@ with keywords in 'position-try-options',
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without using ''@position-try'' at all.
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- <!-- Big Text: -bounds
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-
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- ████▌ ███▌ █▌ █▌ █ █▌ ████▌ ███▌
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- █▌ █▌ █▌ █▌ █▌ █▌ █▌ █▌ █▌ █▌ █▌ █▌
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- █▌ █▌ █▌ █▌ █▌ █▌ ██▌ █▌ █▌ █▌ █▌
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- ████▌ █████ █▌ █▌ █▌ █▌ █▌▐█ █▌ █▌ █▌ ███▌
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- █▌ █▌ █▌ █▌ █▌ █▌ █▌ ██▌ █▌ █▌ █▌
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- █▌ █▌ █▌ █▌ █▌ █▌ █▌ █▌ █▌ █▌ █▌ █▌
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- ████▌ ███▌ ███▌ █▌ ▐▌ ████▌ ███▌
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- -->
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-
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- Applying Stronger Fallback Bounds: the 'position-fallback-bounds' property {#fallback-bounds}
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- --------------------------------------------------------------------------
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-
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- When an element using [=anchor positioning=]
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- is using ''position: absolute'' ,
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- it determines whether or not it's overflowing
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- (and thus should try a different fallback position)
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- by looking at its (scroll-adjusted) [=inset-modified containing block=] .
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- By carefully selecting where in the DOM
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- the positioned element lives,
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- and what element establishes its containing block,
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- you can choose a useful element
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- to use for its overflow bounds.
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-
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- When using ''position: fixed'' ,
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- or things like the Popover API
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- that use the [=top layer=] ,
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- you lose this ability;
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- their containing block is always the viewport
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- or the root element's containing block.
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- The 'position-fallback-bounds' property
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- restores this ability,
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- allowing an element to explicitly select
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- what element it wants to use
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- for checking overflow against.
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-
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- <pre class=propdef>
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- Name : position-fallback-bounds
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- Value : normal | <<dashed-ident>>
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- Initial : normal
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- Applies to : [=absolutely positioned=] elements
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- Inherited : no
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- Animation type : discrete
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- </pre>
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-
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- <dl dfn-type=value dfn-for=position-fallback-bounds>
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- : <dfn>normal</dfn>
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- :: The element uses its normal (scroll-adjusted, inset-modified) containing block
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- to determine if it's overflowing
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- for the purpose of selecting a [=position options list=] entry.
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-
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- : <<dashed-ident>>
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- ::
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- In addition to checking overflow against its containing block,
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- as per ''position-fallback-bounds/normal'' ,
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- the element checks against its <dfn dfn for>additional fallback-bounds rect</dfn> .
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-
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- The [=additional fallback-bounds rect=]
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- is the [=padding box=]
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- of the result of determining the [=target anchor element=]
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- given this element and the specified <<dashed-ident>> .
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- If there is no such [=target anchor element=] ,
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- there is no [=additional fallback-bounds rect=] .
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-
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- Issue: padding-box? Or content-box? Should it be controllable?
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- </dl>
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-
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- Issue: Or should this just be a more generic CSS Position ability,
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- where any abspos can select a specific element as its containing block?
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- Presumably still using the 'anchor-name' to specify it,
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- and applying the same constraints as described here,
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- to ensure proper ordering of layout
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-
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<!-- Big Text: apply
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