simon.schönbeck.dk

Tag: Mozilla

  • Fedora 44 and Firefox 154 crashing: “the specified toplevel id is already used”

    It does not happen often but today after rebooting Fedora Kinoite since the previous OS update Firefox crashed and would no longer load. This is a big issue since we all rely on the browser for everything plus the fact that my session includes tons of open windows and tabs which I would rather not lose.

    Luckily I already had a Flatpak version of Firefox installed from previously which I rarely use. It was installed for some codec issues with Ubiquiti Unifi Protect as well as for certain Youtube videos. This version does not contain all my user profile data or session but at least I could start digging around.

    A couple of weeks ago the Firefox Fedora package maintainer enabled KDE’s session restore feature (not the same as Firefox’s own session restore). However this broke the compatibility with Wayland crashing with “the specified toplevel id is already used“. To be fair I am not too much into the inner workings of XDG, so I tried to just get a work-around.

    The obvious one of starting in X11 actually worked. It launched Firefox and even restored my session. But it was utterly laggy compared to the smoothness of Wayland. If you want to try simply run this in the console:

    MOZ_ENABLE_WAYLAND=0 firefox

    Fortunately I am not the only user affected so there were a few bugs about the issue of which #2059617 has become the principal. Comment 10 mentioned the option to disable the Wayland session and it worked flawlessly. Find your Firefox profile in your home directory (e.g. $HOME/.mozilla/firefox/xxxxx.default-release) and add this line to the end of prefs.js:

    user_pref("widget.wayland.session-management.enabled", false);

    Now restart Firefox and all should be back to normal, Wayland working and your browser session restored.

    I left a comment in the same bug in case anyone needs to get up and running quickly. Hopefully a fix will be out soon so people that are not aware of these work-arounds can launch Firefox again.

  • Running several Firefox versions simultaneously

    Ever been in the need of running more than one instance of Mozilla Firefox? Well, I have. Multiple times.

    I use Firefox for my browsing and development. Combining both in the same profile has been a pain many times especially when ones development is intensive leading to high memory and CPU consumption unfortunately ending with a browser crash.

    Some time ago I starting using Firefox Beta since it included the Sync feature built-in. At some point I wanted to revert back to the release version again as the add-ons needed to be ready for Beta as well and it could take the add-on authors some time to update leaving them disabled till then.

    The easiest thing is to run two or more versions simultaneously of Firefox which provides you with increased flexibility, especially if you do web development of any type.

    To proceed simply download another version of Firefox and install selecting the custom choice. Make sure you install it in a different path than your current Firefox installation.

    The key to get more than one instance of Firefox running is to use multiple profiles. To create an additional profile for your next version open the command prompt (if on Windows) and type the following:

    "C:\Program Files\Mozilla Firefox" -profilemanager -no-remote

    Obviously change the path to match your own system if needed.

     

     

    Now the profile manager should be open and you can simply create a new profile and call it something else like e.g. “BETA”. Then click “Exit” afterwards to quit the profile manager.

     

     

    Next you need to edit the launcher of your newest installation of Firefox, by right-clicking its icon in the Start menu and selecting Properties. At the first text box add the following to the path:

    -P yournewprofilename -no-remote

    So it looks something like this:

    "C:\Program Files\Mozilla Firefox Beta\firefox.exe" -P BETA -no-remote

     

    Save and launch your second instance of Firefox by clicking on the same icon. You should now see two different “Firefox.exe” processes in your task manager.

     

     

    In that same screen you were before you can also change the title and icon itself so that it is easier to distinguish which version is which.