Thunderbird loses message cache on restart

[castanearie]

Describe the bug

Every time I quit and restart Thunderbird, it has to download all my emails again, which also causes it to notify me about unread email every time.

What did you expect to happen?

I expect Thunderbird to keep a cache of already downloaded messages, which would cause it to only notify me about unread emails once.

Output of bootc status

● Booted image: ghcr.io/ublue-os/aurora-dx:stable
        Digest: sha256:99afd1d585814043018fb243e1f774825d9a720cf7e317daccf66e528fe4f5ba (amd64)
       Version: 42.20250817.1 (2025-08-17T06:07:01Z)

  Rollback image: ghcr.io/ublue-os/aurora-dx:stable
          Digest: sha256:ad5d7e5d14abbde6b6628d63d4c5a19ed10ecec8ac8824df88a93d48bd098bf6 (amd64)
         Version: 42.20250810.1 (2025-08-10T06:07:11Z)

Output of groups

$USER wheel docker incus-admin libvirt plugdev

Extra information or context

This happened once in the past, and I think back then I cleared my Thunderbird user data and added all my accounts again manually. Now this bug appeared again after upgrading (see bootc status above). I tried deleting my user data and importing a profile backup, as I didn't want to add everything manually again, but the bug persisted.

[repires]

AI Generated:

Thunderbird is installed as a system Flatpak on Bluefin, and there are no overlays, scripts, or configuration files in Bluefin that manipulate Thunderbird's data directories or cache persistence. The system's Flatpak handling is default except for Firefox config injection, so Thunderbird's cache loss after upgrade is not due to any explicit Bluefin customization. The issue appeared after a system upgrade, and attempts to reset user data and restore profiles did not resolve it. No similar support threads or recent pull requests address Thunderbird cache loss or Flatpak persistence issues after upgrades, except for the original report itself. If the problem persists, it may be related to Flatpak sandboxing or upstream Thunderbird/Flatpak packaging rather than Bluefin-specific changes. You may want to check Flatpak permissions with Flatseal and verify where Thunderbird is storing its profile and cache data, as well as monitor upstream Flatpak and Thunderbird forums for related reports or fixes.

Sources:

• Thunderbird Flatpak packaging in Bluefin
• Bluefin PR #2904 - Flatpak list centralization
• Original issue report

[castanearie]

Going to close this as Thunderbird has been behaving well after reinstalling it again, even through the Fedora 43 upgrade. Should the issue appear again, I will file the issue upstream and give an update here.