Bug 1582866 - Make the inspector extension sidebar overflow. r=rpl.

Differential Revision: https://phabricator.services.mozilla.com/D47273

--HG--
extra : moz-landing-system : lando

devtools/client/inspector/extensions/components/ExtensionSidebar.js

@@ -89,9 +89,6 @@ class ExtensionSidebar extends PureComponent {
       {
         id,
         className,
-        style: {
-          height: "100%",
-        },
       },
       sidebarContentEl
     );

devtools/client/themes/inspector.css

@@ -191,3 +191,9 @@ iframe {
   height: 100%;
   width: 100%;
 }
+
+/* Extension Sidebar */
+.inspector-tabpanel.extension-sidebar {
+  height: 100%;
+  overflow-y: auto;
+}