Merge pull request #23441 from nullaus/bug1058722

bug 1058722 - Add ability to filter stack when invoking the task manager...
(cherry picked from commit 472804d7de2797e87fb4cceb32d51aa1cfc10d6f)
Bug 1059690 - Rocket bar close button css fix r=kgrandon
Bug 1059842 - Rocketbar app icon overflow r=kgrandon
Bug-1054352, Bug-938279, Bug-1046955: FTU updates. r=francisco,sfoster
Bug 1061931 - [Search App] String Change: FTU search suggestion r=Pike
Bug 1061932 - [Email] Cannot edit Email body when using an Outlook account
Merge pull request #23601 from crh0716/1061387

Bug 1061387 - Replace the string 'browser privacy' with 'browsing privacy' r=eragonj
Bug 1056268 - [Contacts] when importing contacts search function is missing functionality
Merge pull request #23654 from nullaus/v2.1

Merge pull request #23441 from nullaus/bug1058722