Updated DevTools pending CHANGELOG

Author: Brian Vaughn

packages/react-devtools/CHANGELOG.md

@@ -8,6 +8,13 @@
 
   <!-- Upcoming changes go here -->
 
+#### Features
+* Re-enabled "copy" prop/state/hooks context menu option for Firefox ([bvaughn](https://github.com/bvaughn),[rpl](https://github.com/rpl) in [#17740](https://github.com/facebook/react/pull/17740))
+* Shift+Enter focuses previous search result in Components tree ([Bo-Duke](https://github.com/Bo-Duke) in [#17005](https://github.com/facebook/react/pull/17005))
+* Properly display formatted `RegExp` values in props/state panel([bvaughn](https://github.com/bvaughn) in [#17690](https://github.com/facebook/react/pull/17690))
+#### Bugfix
+* Check `document.contentType` before injecting hook to avoid breaking XML file syntax highlighting in Firefox ([bvaughn](https://github.com/bvaughn) in [#17739](https://github.com/facebook/react/pull/17739))
+* Fix standalone UI not responding to mouse interactions due to `webkit-app-region` style ([cwatson88](https://github.com/cwatson88) in [#17584](https://github.com/facebook/react/pull/17584))
 </details>
 
 ## 4.3.0 (December 20, 2019)