Thunderbird flatpak fails to start after updating system to 2025/10/18 uninstalling the flatpak and installing the rpm version works properly. Reproducible: Always Steps to Reproduce: 1.Update system 2.Reboot 3.Click on Thunderbird Actual Results: After about 10sec a popup notification of app failure occurs, before first display. Expected Results: Normal Thunderbird startup Additional Information: Xeon gen4, 28GB ram, 92% free disk.
Same behavior for me on Fedora Workstation 42. This is about the Fedora-Flatpak. According to a report on the forum (https://discussion.fedoraproject.org/t/thunderbird-dumps-after-today-flatpack-fc42sb-upgrade/169260/), the version from flathub is not affected. $ flatpak run net.thunderbird.Thunderbird [2] Sandbox: CanCreateUserNamespace() clone() failure: EPERM [Parent 2, Main Thread] WARNING: Could not load a pixbuf from icon theme. This may indicate that pixbuf loaders or the mime database could not be found.: 'glib warning', file /builddir/build/BUILD/thunderbird-140.3.0-build/thunderbird-140.3.0/toolkit/xre/nsSigHandlers.cpp:201 (net.thunderbird.Thunderbird:2): Gtk-WARNING **: 12:57:01.845: Could not load a pixbuf from icon theme. This may indicate that pixbuf loaders or the mime database could not be found. ** Gtk:ERROR:../gtk/gtkiconhelper.c:495:ensure_surface_for_gicon: assertion failed (error == NULL): Failed to load /usr/share/icons/Adwaita/scalable/status/image-missing.svg: Failed to create file “~/.var/app/net.thunderbird.Thunderbird/cache/tmp/gdk-pixbuf-glycin-tmp.TCMSE3”: No such file or directory (g-file-error-quark, 4) Bail out! Gtk:ERROR:../gtk/gtkiconhelper.c:495:ensure_surface_for_gicon: assertion failed (error == NULL): Failed to load /usr/share/icons/Adwaita/scalable/status/image-missing.svg: Failed to create file “~/.var/app/net.thunderbird.Thunderbird/cache/tmp/gdk-pixbuf-glycin-tmp.TCMSE3”: No such file or directory (g-file-error-quark, 4) Redirecting call to abort() to mozalloc_abort
Same here...
same for fedora flatpak $ flatpak run net.thunderbird.Thunderbird [2] Sandbox: CanCreateUserNamespace() clone() failure: EPERM [Parent 2, Main Thread] WARNING: Could not load a pixbuf from icon theme. This may indicate that pixbuf loaders or the mime database could not be found.: 'glib warning', file /builddir/build/BUILD/thunderbird-140.3.0-build/thunderbird-140.3.0/toolkit/xre/nsSigHandlers.cpp:201 (net.thunderbird.Thunderbird:2): Gtk-WARNING **: 13:16:16.589: Could not load a pixbuf from icon theme. This may indicate that pixbuf loaders or the mime database could not be found. ** Gtk:ERROR:../gtk/gtkiconhelper.c:495:ensure_surface_for_gicon: assertion failed (error == NULL): Failed to load /usr/share/icons/Adwaita/scalable/status/image-missing.svg: Failed to create file “~/.var/app/net.thunderbird.Thunderbird/cache/tmp/gdk-pixbuf-glycin-tmp.ZEO0E3”: No such file or directory (g-file-error-quark, 4) Bail out! Gtk:ERROR:../gtk/gtkiconhelper.c:495:ensure_surface_for_gicon: assertion failed (error == NULL): Failed to load /usr/share/icons/Adwaita/scalable/status/image-missing.svg: Failed to create file “~/.var/app/net.thunderbird.Thunderbird/cache/tmp/gdk-pixbuf-glycin-tmp.ZEO0E3”: No such file or directory (g-file-error-quark, 4) Redirecting call to abort() to mozalloc_abort
I had a similar error. not to sure if I had this path "/builddir/build/BUILD/thunderbird-140.3.0-build/thunderbird-140.3.0/toolkit/xre/nsSigHandlers.cpp" in mine, but I did remove the following environment variable via Flatseal TMPDIR=~/.var/app/net.thunderbird.Thunderbird/cache/tmp This seems to made it work again. So I am asking myself if this change of the tmpdir is important as flatpak already isolates the normal /tmp/ access in some manner.
(In reply to Attura from comment #4) > I had a similar error. > > not to sure if I had this path > "/builddir/build/BUILD/thunderbird-140.3.0-build/thunderbird-140.3.0/toolkit/ > xre/nsSigHandlers.cpp" in mine, but I did remove the following environment > variable via Flatseal > TMPDIR=~/.var/app/net.thunderbird.Thunderbird/cache/tmp > > This seems to made it work again. > > So I am asking myself if this change of the tmpdir is important as flatpak > already isolates the normal /tmp/ access in some manner. Same fix (use flatseal to remove TMPDIR from Environment) worked for me on Fedora 42. Thank you Attura for the pointer.
I have the same issue: flatpak run net.thunderbird.Thunderbird [2] Sandbox: CanCreateUserNamespace() clone() failure: EPERM [Parent 2, Main Thread] WARNING: Could not load a pixbuf from icon theme. This may indicate that pixbuf loaders or the mime database could not be found.: 'glib warning', file /builddir/build/BUILD/thunderbird-140.3.0-build/thunderbird-140.3.0/toolkit/xre/nsSigHandlers.cpp:201 (net.thunderbird.Thunderbird:2): Gtk-WARNING **: 16:35:37.883: Could not load a pixbuf from icon theme. This may indicate that pixbuf loaders or the mime database could not be found. ** Gtk:ERROR:../gtk/gtkiconhelper.c:495:ensure_surface_for_gicon: assertion failed (error == NULL): Failed to load /usr/share/icons/Adwaita/scalable/status/image-missing.svg: Failed to create file “~/.var/app/net.thunderbird.Thunderbird/cache/tmp/gdk-pixbuf-glycin-tmp.T2WWE3”: No such file or directory (g-file-error-quark, 4) Bail out! Gtk:ERROR:../gtk/gtkiconhelper.c:495:ensure_surface_for_gicon: assertion failed (error == NULL): Failed to load /usr/share/icons/Adwaita/scalable/status/image-missing.svg: Failed to create file “~/.var/app/net.thunderbird.Thunderbird/cache/tmp/gdk-pixbuf-glycin-tmp.T2WWE3”: No such file or directory (g-file-error-quark, 4) Redirecting call to abort() to mozalloc_abort
(In reply to David Williams from comment #5) > (In reply to Attura from comment #4) > > I had a similar error. > > > > not to sure if I had this path > > "/builddir/build/BUILD/thunderbird-140.3.0-build/thunderbird-140.3.0/toolkit/ > > xre/nsSigHandlers.cpp" in mine, but I did remove the following environment > > variable via Flatseal > > TMPDIR=~/.var/app/net.thunderbird.Thunderbird/cache/tmp > > > > This seems to made it work again. > > > > So I am asking myself if this change of the tmpdir is important as flatpak > > already isolates the normal /tmp/ access in some manner. > > Same fix (use flatseal to remove TMPDIR from Environment) worked for me on > Fedora 42. Thank you Attura for the pointer. Same issue here, installed flatseal and (through the gui) deleted the TMPDIR setting, Thunderbird now loads. I'll note that I never got an application error pop-up, it just failed silently. I had to do "flatpak run net.thunderbird.Thunderbird" to see error messages.
In addition to previous comments: another workaround (without using flatseal) would be to run `flatpak override --user --unset-env=TMPDIR net.thunderbird.Thunderbir`.
Moved TMPDIR env from the flatpak run parameters: https://src.fedoraproject.org/flatpaks/thunderbird/pull-request/1 to the launch script (to still be able to open attachments in third party apps): https://src.fedoraproject.org/rpms/thunderbird/c/3b4cf8bcd79c0f38b7d7b218b56af67051589d3b?branch=rawhide