[css-grid-2] Mention gutter, update changelog w3c#9935

Author: fantasai

css-grid-2/Overview.bs

@@ -39,9 +39,12 @@ spec:css-flexbox-1;
 		text: specified size
 		text: content size
 		text: transferred size
+		text:order-modified document order
 	type:value
 		text:flex
 		text:inline-flex
+	type:property;
+		text:order
 spec:css-pseudo-4; type:selector;
 	text:::first-line
 	text:::first-letter
@@ -3880,7 +3883,7 @@ Subgrids</h2>
 			the occupied track closest to that edge of the subgrid.
 			The hypothetical item’s sizes are taken from the sizes of the largest such item
 			of each span size,
-			and are additionally inflated by the subgrid’s own margin/border/padding
+			and are additionally inflated by the subgrid’s own margin/border/padding/gutter
 			at that edge.
 			Correspondingly, the hypothetical item’s span is taken
 			from that same real item’s span,
@@ -5451,6 +5454,18 @@ Changes since the <a href="https://www.w3.org/TR/2020/CRD-css-grid-2-20201218/">
 						and does not affect track sizing.)</ins>
 				</ul>
 			</blockquote>
+		<li>
+			Clarified that the [=scrollbar gutter=] is accounted for alongside the margin/border/padding
+			when calculating the contribution of the subgrid itself
+			(not just when accounting for its children).
+			(<a href="https://github.com/w3c/csswg-drafts/issues/9935">Issue 9935</a>)
+			<blockquote>
+				<p>For each edge of a non-empty [=subgrid=],
+				to account for the subgrid’s margin/border/padding <ins>(and any scrollbar gutter)</ins> at that edge,
+				&hellip;
+				and are additionally inflated by the subgrid’s own margin/border/padding<ins>/gutter</ins>
+				at that edge.
+			</blockquote>
 		<li>
 			Also incorporated <a href="https://www.w3.org/TR/2025/CRD-css-grid-1-20250326/#changes-202012">all changes to CSS Grid Level 1 since its previous publication</a>.
 	</ul>