[css-overflow-3] Add status text

Author: fantasai

css-overflow-3/Overview.bs

@@ -16,6 +16,11 @@ Abstract: This module contains the features of CSS relating to scrollable overfl
 !Change Log: <a href="https://hg.csswg.org/drafts/log/tip/css3-overflow/Overview.src.html">from 31 July 2012 to 27 March 2013</a>
 Ignored Vars: B, P
 Ignored Terms: padding edge
+Status Text: <strong>This update trims away most of the experimental new ideas
+   for handling overflow that were described in the <a href="https://www.w3.org/TR/2013/WD-css-overflow-3-20130418/">previous Working Draft</a>.
+   These ideas are not abandoned; they are merely <a href="https://drafts.csswg.org/css-overflow/">deferred until Level 4</a>.</strong>
+   Level 3 is focused solely on completing a spec for the existing, shipped 'overflow' features;
+   work will resume on fragmented overflow and other fun things once this is completed.
 </pre>
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