Resolve w3c#4693, editorial

Author: tantek

css-scrollbars-1/Overview.bs

@@ -9,7 +9,8 @@ ED: https://drafts.csswg.org/css-scrollbars/
 Repository: https://github.com/w3c/csswg-drafts/tree/master/css-scrollbars-1 css-scrollbars
 Editor: Tantek Çelik, Mozilla https://www.mozilla.org/, http://tantek.com/contact, w3cid 1464
 Editor: Rossen Atanassov, Microsoft, ratan@microsoft.com, w3cid 49885
-Abstract: CSS Scrollbars standardizes the ability to color scrollbars introduced in 2000 by Windows IE 5.5. 
+Abstract: CSS Scrollbars standardizes the ability to style scrollbar controls, such as their color,
+          introduced in 2000 by Windows IE 5.5. 
           This is useful when building web applications which use color schemes very different from 
           the appearance of default platform scrollbars.
 Link Defaults: css-color-3 (property) color
@@ -27,19 +28,25 @@ maintained in the W3C csswg-drafts GitHub repository as css-scrollbars-1
 Scope</h3>
 <em>This subsection is non-normative.</em>
 
+The CSS Scrollbars Module is specifically for styling scrollbar controls themselves, 
+e.g. their color &amp; width in Level 1, and not their layout nor whether any content is scrollable. 
+All layout impacts and content scrollability are specified in the 
+<a href="https://drafts.csswg.org/css-overflow/">CSS Overflow Module</a>.
+
 Based on
 <a href="https://www.w3.org/wiki/Css-scrollbars#Use-cases">documented use-cases</a>,
 there are three main use-cases around scrollbars this module intends to resolve:
 <ol>
- <li>Color scrollbars to fit better into the UI of a web application.
- <li>Use thinner scrollbar when the scrolling area is small.
- <li>Build customized scrollbars without affecting scrollability.
+ <li>Coloring scrollbars to fit better into the UI of a web application.
+ <li>Using a thinner scrollbar when the scrolling area is small.
+ <li>Building customized scrollbars without affecting scrollability.
 </ol>
 
-For addressing these use-cases, this module adds properties to control colors and
+For addressing these use-cases, this module adds properties to control the colors and
 width of scrollbars (if any) of an element.
 
-Pseudo-elements for selecting specific parts of a scrollbar is out of scope.
+<h4 id="out-of-scope">
+Pseudo-elements for selecting specific parts of a scrollbar are out of scope.
 The WebKit implementation of pseudo-elements for scrollbar is
 considered to be a feature mistakenly exposed to the web.
 Main concerns against the pseudo-elements approach are:
@@ -50,6 +57,10 @@ Main concerns against the pseudo-elements approach are:
  because authors would need to take not only engine but also platforms into account.
 </ul>
 
+Layout of scrollbars and related or adjacent content, and whether content is scrollable, is out of scope.
+Those features are specified in the 
+<a href="https://drafts.csswg.org/css-overflow/">CSS Overflow Module</a>.
+
 <h3 id="values">
 Value Definitions</h3>
 
@@ -206,9 +217,11 @@ Thanks to the use-cases, prototyping, implementation, and feedback from
 
 This appendix is <em>informative</em>.
 
-This is the First Public Working Draft, no previous draft to describe changes from.
-<!-- This appendix describes changes from the
-<a href="https://www.w3.org/TR/2018/WD-scrollbars-1-2018MMDD/">First Public Working Draft (FPWD) of DD Month 2018</a>.-->
+This appendix describes changes from the
+<a href="https://www.w3.org/TR/2018/WD-css-scrollbars-1-20180925/">First Public Working Draft (FPWD) of 25 Sep 2018</a>.
+<ul>
+<li><a href="https://github.com/w3c/csswg-drafts/issues/4693">#4693</a>: Clarified scope: styling scrollbar controls themselves.</li>
+</ul>
 
 <h2 class="no-num" id="security-privacy-considerations">Appendix C. Considerations for Security and Privacy</h2>