One is that gnome-keyring doesn't whitelist Seahorse in /usr/share/p11-kit/modules/gnome-keyring.module, so its PKCS#11 module doesn't load inside Seahorse at all, cutting off Seahorse from the user's certificates. A merge request (with a patch to remove that whole list and allow loading everywhere) is at https://gitlab.gnome.org/GNOME/gnome-keyring/-/merge_requests/61.
The other is a gcr-3 regression introduced when they migrated from autotools to meson, that left out a resource file from the build. A merge request with my patch is at https://gitlab.gnome.org/GNOME/gcr/-/merge_requests/134 but I am not sure whether the gcr team is making any further gcr-3 releases. It's not yet clear what is happening in future versions, such as gcr-4, as it deleted that file, and it is presumably moving to Seahorse. Seahorse's nielsdg/gtk4 branch with that change was last updated mid-2022 and has not yet been merged to main.
Having applied those patches on Xubuntu 23.04, I can import certificates perfectly. However after import I have to restart Seahorse to see the new certificates, which seems like some other bug.
There are at least 2 bugs here.
One is that gnome-keyring doesn't whitelist Seahorse in /usr/share/ p11-kit/ modules/ gnome-keyring. module, so its PKCS#11 module doesn't load inside Seahorse at all, cutting off Seahorse from the user's certificates. A merge request (with a patch to remove that whole list and allow loading everywhere) is at https:/ /gitlab. gnome.org/ GNOME/gnome- keyring/ -/merge_ requests/ 61.
The other is a gcr-3 regression introduced when they migrated from autotools to meson, that left out a resource file from the build. A merge request with my patch is at https:/ /gitlab. gnome.org/ GNOME/gcr/ -/merge_ requests/ 134 but I am not sure whether the gcr team is making any further gcr-3 releases. It's not yet clear what is happening in future versions, such as gcr-4, as it deleted that file, and it is presumably moving to Seahorse. Seahorse's nielsdg/gtk4 branch with that change was last updated mid-2022 and has not yet been merged to main.
Having applied those patches on Xubuntu 23.04, I can import certificates perfectly. However after import I have to restart Seahorse to see the new certificates, which seems like some other bug.