http://recordit.co/GdonfCA8Jw Test system addon from older nightly to patched nightly (local build) does not work since ALL system addons does not load at first start (can't see pocket, screenshots). Re-open the browser and add-ons works normal again. It might only happens while manual select the same profile. Manual test steps on OSX: 1. download 2017-06-28 nightly $ sudo pip install mozdownload $ mozdownload -t daily --date 2017-06-28 2. drag FirefoxNightly.app from dmg to somewhere 3. create a new profile with ./FirefoxNightly.app/Contents/MacOS/firefox -P Then open nightly, the pocket and screenshot icon will shown. Close the app. 4. Open the local nightly, with same profile ./mach run -P pocket and screenshot system add-ons are gone 5. reopen local nightly ./mach run -P add-ons work normally again expect result: add-ons work normally when start with older profile

Does this affect the Photon onboarding? Need a [photon-onboarding] whiteboard?

(In reply to Fischer [:Fischer] from comment #1) > Does this affect the Photon onboarding? I don't think so, since this should not happen on the official Nightly upgrade path (updating official Nightly to another offical Nightly of a later date).

As https://bugzilla.mozilla.org/show_bug.cgi?id=1377470#c17 No its not

I'm not surprised this doesn't work, the locations of all your installed extensions are stored in the profile. They are updated if the application version changes but in the STR outlined in comment 0, the application version remains fixed at 56.0a1 so we're still trying to load system add-ons from the original application directory (ie the downloaded FirefoxNightly.app/ directory) and that breaks. rhelmer is in the midst of changing how system addons are handled, perhas that work will address this situation too...

I suspect this is a dup of bug 1371273, although that bug probably needs a better summary. As aswan mentioned in comment 4, currently the full path to all extensions is stored in the profile, so changing the location of the application can break that in some cases (although they will work again after another restart per comment 0). I'm also working on moving built-in add-ons into the omni jar (bug 1357205) but since the omni jar is still located in the application directory we still need to do something here. I think the precise fix here is that add-ons that ship with the application should not have full paths in the addons DB which lives in the profile, and should instead be assumed to be relative to the application directory.