Customization failure
Tab Group and Private browser icons appear but are are grayed out and do not work. Also, download helper extension icon does not appear at all. although the extension is current (reinstalled) and the "download" feature is on.. These features work fine on my desktop but not on my laptop (used to work but have stopped). Options setting between the machines are identical. I am afraid to sync because, with my luck, the bad setup will become the common setup.
Wšykne wótegrona (1)
It is possible that there is a problem with the file(s) that store the extensions registry.
Delete the extensions.* files (e.g. extensions.json, extensions.sqlite, extensions.ini) and compatibility.ini in the Firefox profile folder to reset the extensions registry.
New files will be created when required.
See "Corrupt extension files":
- http://kb.mozillazine.org/Unable_to_install_themes_or_extensions
- https://support.mozilla.org/kb/Unable+to+install+add-ons
If you see disabled or not compatible extensions in "Firefox/Tools > Add-ons > Extensions" then click the Tools button at the left end of the Search bar to check if there is a compatibility update available.
If this hasn't helped then also delete possible addons.json and addons.sqlite files.
You can also check for problems with preferences.
Delete possible user.js and numbered prefs-##.js files and rename (or delete) the prefs.js file to reset all prefs to the default value including prefs set via user.js and prefs that are no longer supported in the current Firefox release.
You can use this button to go to the currently used Firefox profile folder:
- Help > Troubleshooting Information > Profile Directory: Show Folder (Linux: Open Directory; Mac: Show in Finder)
- http://kb.mozillazine.org/Profile_folder_-_Firefox