Opening link causes “Firefox is already running, but is not responding” with flatpak

Meta point: this feels to me like a packaging bug that belongs in an issue tracker rather than a discussion forum. Where is the right place to file flatpak packaging bugs?

On F40 I have Firefox installed through Fedora’s flatpak (details below). When I click on a link in another app, it always fails with a popup that says:

Firefox is already running, but is not responding. To use Firefox, you must first close the existing Firefox process, restart your device, or use a different profile.

I imagine such a click ends up running something similar to this, which reproduces the same error message:

$ flatpak run org.mozilla.firefox --new-tab

Many search engine results explain how to kill a stray process that did not exit cleanly. This is not what’s happening here: Firefox is running perfectly fine within its own windows. But talking to it from the outside fails. Maybe because of isolation provided by Flatpak?

These do sound relevant, as about:supports in Firefox does list “Window Protocol: wayland”:

… but they don’t actually help, this still fails with the same error message:

$ flatpak run --env=MOZ_DBUS_REMOTE=1 org.mozilla.firefox --new-tab

Extra info:

$ flatpak info org.mozilla.firefox

Firefox - Web Browser

          ID: org.mozilla.firefox
         Ref: app/org.mozilla.firefox/x86_64/stable
        Arch: x86_64
      Branch: stable
     Version: 125.0.3
     License: GPL-3.0+
      Origin: fedora
Installation: system
   Installed: 253.2 MB
     Runtime: org.fedoraproject.Platform/x86_64/f40
         Sdk: org.fedoraproject.Sdk/x86_64/f40

      Commit: aee94906526e00fa39e7bd035e1426abf59c2660da2d21032cfb492c3c8c3e0a
     Subject: Export org.mozilla.firefox
        Date: 2024-04-30 09:24:23 +0000
      Alt-id: 92f2292e5d654994902673803a3017324ac635d8880b866655f616fddf395a3a

Removed audio

Confirmation that Flatpak is responsible: installing with RPM instead fixes this problem.

It is always good to tracking Issues alias reporting bugs. Here some information how to proceed and which kind of information is needed:

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