[css-align-3][css-inline-3] Only apply margin-edge baseline rule to scroll containers with non-initial baseline-source. #8214

Author: fantasai

css-align-3/Overview.bs

@@ -2196,7 +2196,9 @@ Determining the Baselines of a Box</h2>
 			then the block container has no [=baseline set=].
 
 			However, for legacy reasons
-			a [=block-level=] or [=inline-level=] [=scroll container=]
+			if its 'baseline-source' is ''baseline-source/auto'' (the [=initial value=])
+			a [=block-level=] or [=inline-level=] [=block container=]
+			that is a [=scroll container=]
 			always has a [=last baseline set=],
 			whose baselines all correspond to its [=block-end=] [=margin edge=].
 
@@ -2442,6 +2444,13 @@ Appendix A: Static Position Terminology</h2>
 <h2 id="changes">
 Changes</h2>
 
+	Changes since the <a href="https://www.w3.org/TR/2023/WD-css-align-3-20230217/">17 February 2023 Working Draft</a> include:
+	<ul>
+		<li>Only apply the special margin-edge baseline rule for [=scroll container=] [=block containers=]
+			when 'baseline-source' is its [=initial value=].
+			(<a href="https://github.com/w3c/csswg-drafts/issues/8214">Issue 8214</a>)
+	</ul>
+
 	Changes since the <a href="https://www.w3.org/TR/2021/WD-css-align-3-20211224/">24 December 2021 Working Draft</a> include:
 	<ul>
 		<li>Define the baselines of a [=multi-column container=].

css-inline-3/Overview.bs

@@ -769,6 +769,9 @@ Alignment Baseline Source: the 'baseline-source' longhand</h4>
 		<dd>Specifies <a>last-baseline alignment</a>.
 	</dl>
 
+	See [[css-align-3#baseline-export]]
+	for how to find the baselines of boxes other than [=inline boxes=].
+
 <h4 id="alignment-baseline-property">
 Alignment Baseline Type: the 'alignment-baseline' longhand</h4>