[css-scroll-anchoring] Specify how anchoring interacts with snapping. #4830

Author: tabatkins

css-scroll-anchoring-1/Overview.bs

@@ -19,15 +19,16 @@ Abstract: This spec also proposes an API for web developers to opt-out of this b
 
 <pre class=link-defaults>
 spec:css-box; type:dfn; text:content area
-spec:css22;
+spec:css2;
+	type:dfn; text:line box
+spec:css-sizing-3;
 	type:property;
 		text:max-height
 		text:min-height
 		text:height
 		text:max-width
 		text:min-width
 		text:width
-	type:dfn; text:line box
 </pre>
 <pre class="anchors">
 spec: html; urlPrefix: https://html.spec.whatwg.org/multipage/;
@@ -75,9 +76,15 @@ For readability they have not been repeated explicitly.
 <h2 id='description'>
 Description</h2>
 
-Scroll anchoring works by selecting a DOM node (the <dfn export for=scroll-anchoring>anchor node</dfn>)
+Scroll anchoring attempts to keep the user's view of the document stable across layout changes.
+It works by selecting a DOM node (the <dfn export for=scroll-anchoring>anchor node</dfn>)
 whose movement is used to determine adjustments to the scroll position.
 
+However, if the scroll container is currently [=scroll snap|snapped=] to an element,
+(see [[!CSS-SCROLL-SNAP-1]])
+scroll anchoring is limited to adjustments that would be allowed by [=re-snapping=].
+
+
 <h3 id='anchor-node-selection'>
 Anchor Node Selection</h3>