[css-ui-4] Sigh, inheritance *does* work on the flat tree, I'm dumb.

Author: tabatkins

css-ui-4/Overview.bs

@@ -1979,10 +1979,10 @@ Preventing All Interaction: the 'interactivity' property</h3>
 
 <pre class=propdef>
 Name: interactivity
-Value: auto | normal | inert
+Value: auto | inert
 Initial: auto
 Applies to: all elements
-Inherited: no
+Inherited: yes
 Percentages: N/A
 Computed Value: as specified
 Animation type: discrete
@@ -1995,22 +1995,13 @@ are [=inert=] or not.
 <dl dfn-type=value dfn-for=interactivity>
 	: <dfn>auto</dfn>
 	::
-		The element is [=inert=] if and only if 
-		its [=flat tree=] parent is [=inert=].
-
-	: <dfn>normal</dfn>
-	:: The element is not [=inert=].
+		Unless otherwise specified by the host language,
+		the element is not [=inert=].
 
 	: <dfn>inert</dfn>
 	:: The element is [=inert=].
 </dl>
 
-Note: While 'interactivity' is not an [=inherited=] property,
-by default (when set to ''interactivity/auto'')
-it acts <em>similarly</em> to one,
-except it "inherits" thru the [=flat tree=]
-rather than the usual parent/child relationship.
-
 <div algorithm>
 	When an [=element=] or [=text run=] is <dfn export>inert</dfn>:
 
@@ -2048,23 +2039,18 @@ In these instances, the <{input/disabled}> attribute is probably more appropriat
 
 	<pre highlight=css>
 	@scope ([inert]) to (X) {
-	  interactivity: inert !important;
+		* {
+	  	interactivity: inert !important;
+		}
+	}
+	X {
+		interactivity: auto;
 	}
 	</pre>
 
 	Where the <css>X</css> represents a theoretical selector 
 	matching any elements that "escape" inertness by default,
 	such as modal dialogs.
-
-	This prevents descendants of an element with the <{html-global/inert}> attribute
-	from being un-inerted,
-	but <em>does</em> allow elements that are [=flat tree=] descendants,
-	but not DOM tree descendants,
-	to be set non-inert.
-	For example, a light-tree element
-	slotted into an inert subtree in a shadow DOM
-	could turn off inertness.
-	I assume this is ok?
 </div>