How to Actually Get QT & the KDE Suite of Apps To Work in Non-Plasma Desktop Environments

I couldn’t find a single comprehensive guide out there that I could find on getting KDE (QT) apps to work on any other desktop environment other than KDE (wihout either mismatched dark and light themes or horrible tearing in apps). IT IS VERY POSSIBLE, but you need to install a lot of dependencies.

Install qt5ct-kde qt6ct kvantum-git dolphin kate konsole plasma-desktop

yay -S --needed qt5ct-kde qt6ct kvantum-git dolphin kate konsole plasma-desktop (should work)
You can also use [https://github.com/endeavouros-team/EndeavourOS-packages-lists](https://the endeavour os packagelist ) to get the plasma dependencies (and subsequent packages to remove)

Set the environment variables in /etc/environment/ (just add it on it’s own line) to XDG_CURRENT_SESSION=KDE and reboot.
Log into Plasma and set your application style to kvantum and set the theme to the respective color scheme (KvArc for example in Kvantum and color schemes). This is because you can’t import kde color schemes easily to qt5ct and qt6ct. Set your icon theme to the one you want to use (for me that was Fluent Dark), change your cursor to the one you want (again Fluent for me)
After doing that log back into xfce/qtile/gnome/ whatever your using and open up qt5ct, sudo qt5ct, qt6ct, and sudo qt6ct. In ALL of them set the application theme to kvantum, leave the color scheme as default. Go to fonts and set General: Noto Sans (Regular) 10 Fixed width: Monospace (Regular) 10 DO NOT create a fonts.conf. Set the icon theme to a dark variant, unless your insane and like light themes. Do this for both root and user qt5ct and qt6ct.
Finally, comment out $XDG_CURRENT_SESSION=KDE and add QT_QPA_PLATFORMTHEME=qt5ct and reboot. Now you should have a consistent dark theme for every app you use, including configuration settings (right click > configure dolphin). You can get rid of plasma-desktop, but I keep it around just in case I need to change my color scheme/kvantum theme. I have gotten this to work with both breeze and lightly but I still need to test if it’ll work.
NOTE: I’ve copied this over from my github page where I have other general notes and whatnot.

UPDATE: So Lightly, Classik (which I believe is changing it’s name to klassy) and Breeze I’ve been able to work just fine, basically the same steps but instead of using kvantum you just select the other.

Please let me know if this works for you all. I’ve been able to reproduce it three times, but haven’t had anyone to test on their end.

Has anyone been able to confirm or deny this working?

Have you read this?

https://discovery.endeavouros.com/applications/uniform-theme-and-fonts-for-qt-apps-in-gtk-environments/2021/05/

https://wiki.archlinux.org/title/Uniform_look_for_Qt_and_GTK_applications

I run a few KDE/QT apps under XFCE - qbittorrent, qalculate-qt, pyside6 to new a new - and I’ve never had to install kvantum (but I did - and not the git version - because it looks good), konsole (no dependencies that matter), kate, plasma-desktop, or dolphin (why need another file manager???).

Every Kvantum theme was available right away, so there was no additional config needed, except for choosing the desired theme (using KvBlender).

In my tests even if you installed kvantum going into settings would have a broken theme, this is the way I’ve learned on how to use truly any app in any desktop environment, because imo kde has hands down the best suite of apps

Yes I have, multiple times, and it only works for a handfull of qt apps. Ive tested everyway suggested too.

There might be a way to bypass having to install KDE, but I need someone to test it for me. I downloaded arc-kde and the color scheme showed up in qt5ct, need someone to test it for me and see if it shows up on their end