What preference or option allows the icons for add-ons to show in the area to the right of the address bar?
In order to fix a problem I was having with a Firefox add on, I was advised to uninstall and reinstall Firefox. I backed up my Profile folder first and then did the uninstall/install. I then reinstalled the add-on that had been having a problem. The good news is that my problem was resolved. The bad news was that I needed to restore as much of my old configuration setup and things like history and bookmarks. The latter item was fairly simple, I just had to copy places.sqlite from my old profile folder to the new profile folder. Then I reinstalled the other add-ons which had been installed on my previous config. So far so good. The next task, which was probably the most complex and possibly troublesome was to actually restore all of the changes that had been made by me and Firefox itself to the actual config options. Although I didn't keep track over the years, I had made dozens of config changes to fix problems or to get Firefox to work the way I wanted it to. These changes were all made after searching on sites like this, so they were not done capriciously. So I wanted to restore these changes. I copied the prefs.js file from my old profile into the new profile. The only problem I noticed was the that the icons for all the add-ons disappeared from the area to the right of the address bar and search bar. I don't know what this area is called, but it also includes the 'hamburger" icon to open the Firefox menu.
Can anyone tell me which config option this is, or is it controlled by something else?
Alle svar (3)
So why does a addon problem have to do with a uninstall and reinstalling firefox? I would uninstall and reinstall the addon not the browser itself. Whom said to do that?
Westend: It was Norton/Symantec support that made the recommendation. I wasn't convinced that it would correct the issue, and even if it did, I thought it was overkill, but I felt like I needed to "humor" them in order to elicit further assistance. We had already tried removing and reinstalling the add-on; that didn't work. I have a theory that the problem was due to one of the files/elements in either the Extensions or browser-entension-data folders (in the Firefox Profile folder) becoming corrupted. In retrospect, I wonder if simply deleting the entries for the add-on and then reinstalling it would work, but it was too late at that point. If I ever have a recurrence of the original issue, I'll try out my theory. Now that I've answered your questions, do you have any ideas about my question as to which Firefox preference might have caused the icons for the add-ons to disappear?
Firefox stores toolbar customization in browser.uiCustomization.state in JSON format. Note that there might be more preferences that aren't compatible across profiles and usually best is to check prefs.js and only copy lines you need.
See also comments in the Firefox source code.