Affected versions: latest Aurora 46.0a2 and Nightly 47.0a1 (from 2016-02-02), e10s enabled/disabled Affected platforms: Ubuntu 14.04 32-bit, Mac OS X 10.9.5 and Windows 7 64-bit Steps to reproduce: 1. Launch Firefox with a clean profile. 2. Click on Menu panel (Hamburger button). 3. Select Customize. 4. Drag Pocket button to the Menu Panel. 5. Move at least 1 more button from the toolbar to the Menu panel. 6. Click 'Restore Defaults' button. 7. Repeat step 6. Expected results: 'Restore defaults' button is not actionable. Actual results: Pocket button no longer displayed in the toolbar, Menu Panel nor Additional Tools and Features. Additional notes: 1. Screen recording: https://goo.gl/hYyyqT 2. Via about:config page, 'extensions.pocket.enabled' pref is still set to true and 'browser.uiCustomization.state' points that the button is placed in nav-bar: 'nav-bar': [ 'urlbar-container', 'search-container', 'bookmarks-menu-button', 'pocket-button', 'downloads-button', 'home-button', 'loop-button' ], 3. Unaffected version - 45 beta 2 (Build ID: 20160201143558) and 44.0RC build 3 (Build ID: 20160123151951). 4. Regression range: Last good revision: 0c12d4229be0068eb1b9beb5064b800f12143f20 First bad revision: 3ba655f6bc67660a2dcfc4c2a5b3d0d17714f53d Pushlog: https://hg.mozilla.org/integration/fx-team/pushloghtml?fromchange=0c12d4229be0068eb1b9beb5064b800f12143f20&tochange=3ba655f6bc67660a2dcfc4c2a5b3d0d17714f53d Regressed by 3ba655f6bc67 Shane Caraveo — Bug 1215694 move pocket to a system addon

Tracking for 46+ since this is a recent regression.

Marking fixed as this is now tracked in the duplicate bug.