[css-overflow-3] Update Changes section

Author: fantasai

css-overflow-4/Overview.bs

@@ -1713,15 +1713,22 @@ Answers are provided below.
 
 <h2 id="changes" class="no-num">
 Changes</h2>
+
+<h3 id="recent-changes">
+Recent Changes</h3>
+
+	Significant changes since the <a href="https://www.w3.org/TR/2017/WD-css-overflow-4-20170613/">June 2017 Working Draft</a> include:
+	<ul>
+		<li>Moved in the definition of 'text-overflow' from [[CSS-UI-4]].
+		<li>Moved the core definition of 'scrollbar-gutter' to [[CSS-OVERFLOW-3]]
+				(it will be copied back here once this specification is undiffed)
+				and shift exploratory 'scrollbar-gutter' extension ideas into an appendix.
+	</ul>
+
 <h3 id="changes-l3">
 Changes Since Level 3</h3>
 
-The following changes were made to this specification since the
-<a href="https://drafts.csswg.org/css-overflow-3/">CSS Overflow Module Level 3</a>:
-
-<ul>
-	<li>The Fragmentation of overflow, Paginated overflow, and Fragment overflow sections and subsections have been removed form Level 3 and moved to Level 4.
-</ul>
+	ISSUE: TBD
 
 <h2 class=no-num id="acknowledgments">
 Acknowledgments</h2>