Mozilla allowed one of their security certificates to expire which affected a LOT of users, me included. The result was a yellow warning bar in the browser stating that some add-ons have been disabled. Indeed, all but 2 of mine were disabled.
The problems begin when one attempts to re-enable the affected add-ons only to find that there is apparently no way to do this from within the Firefox UI.
The fix that worked for me comes from ghacks.net and it's especially well suited for anyone that disables Mozilla's 'Studies' feature, but it should work in all cases. Following is the corrected and properly formatted code and instructions.
- Exit Firefox
- In your Firefox profile, make a backup of extensions.json and open the original in a code editor
- Replace all instances of
"appDisabled":truewith"appDisabled":false - Replace all instances of
"signedState":-1with"signedState":2 - Save your changes, then set the file permissions to 'read only'
- Restart Firefox, load
about:addonsand make sure to select the 'Extensions' menu - Disable and re-enable all of the disabled add-ons
!!! IMPORTANT !!! Make good and sure you remember to restore the proper permissions for extensions.json after this issue is resolved (a day or so?) and you probably do not want to install or remove any extensions while the file is set to 'read only'.
The above method does not work. Firefox creates a new file named extensions.json.tmp when it can't write to extensions.json and then disables add-ons again.
sorry to hear that – it worked for me – also Moz released a new version with the fix integrated – did you update yet?