Qt5 apps do not use GTK2 theme in Ubuntu 23.04 Beta

Qt apps like RSS Gurad, qBittorrent do not use GTK2 theme like they were in Ubuntu 22.10. Even after installing qt5-style-plugins and exporting the settings into my .profile.

Could you install all updates, log out, then log back in?

There was a mutter fix for some theming issues released a few days ago.

I have done that already, anything else I should try?

Any update on this? I do see it working with live image, which I have since installed on my computer but still getting same issue.

Try adding a new user and then log in as the new user.

If it works, then the problem is your user’s configuration. You might have set something to try to work around an issue that has since been fixed, but now your workaround is getting in the way.

Did that and it didn’t work. I also tested a newer daily build worked in that (live session). So I backed up my files, and reinstalled with the home partition formatted and it was back to having the issue. It might be related to my hardware and this version of wayland/mutter. ¯_(ツ)_/¯

With latest rounds of updates and using xorg qt5 apps are looking great. Just in wayland they look bad.

I’m dealing with the exact same issue, Qt5 apps on Wayland doing no integrations (specifically running QBittorrent & Strawberry). They take configs from Qt5ct, but that’s about it. Qt6 seems to work better, at least they move window controls to the left as with my GTK setup. No other Qt-related configs on my end. Are Qt5 apps just broken like that on 23.04? Any news on this?

Submitted a bug: https://bugs.launchpad.net/oem-priority/+bug/2017521

I added the line export QT_QPA_PLATFORM=“xcb” in .profile at the Home folder and the qt apps are working much better

No still the same for me.

Try open the app via terminal and add -platform xcb at the end
For example kdenlive -platform xcb

That works, not it should work without having to do that. Do you qt5-style-plugins installed?

Yes i have qt5-style-plugins installed
It’s strange because adding export QT_QPA_PLATFORM=“xcb” to the profile should force
QT to use xcb

I can try again, I did put “xcb” within quotes and also tried w/o quotes and still no luck.

Im sorry it is without quotes and you have to reboot the machine after, you can find more sugestions
on this thread https://discussion.fedoraproject.org/t/bug-with-qt-software-digikam-texstudio/74839/4

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Thanks for the link. I got it working. I was putting in “PLATFORMTHEME” instead of “PLATFORM”. Now RSSGuard looks like it belongs on my system.
Screenshot from 2023-04-29 07-05-33

It is so inconsistent. After rebooting my computer it is back to being awful. :frowning:

Maybe it is possible to have consistent look for GTK2 apps. But also it should be possible(maybe only for SNAPCRAFTERs) to have list all apps which uses some toolkit like GTK2 or Motif seems impractical, but when there is for LTS 5+5 years of support it would be great to look for QT5 or GTK3 apps looking for some care(or notify maintainers) for next upgrade or also would maybe mean that maybe such application should have special tag like obsolete, retro, vintage or someone know what it does :jack_o_lantern:

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