Provide a Consistent Theme for Qt Applications

[FromLinuxWithLove]

Please consider setting up a Qt theme such as Fluent-kde by default for a more integrated look and feel with Qt applications such as KeePassXC.

I set it up myself using Kvantum, but it would be great to have this available out of the box. Many people pay attention to such details, as it makes the Distro look and feel more polished.

To get it working, I also had to modify my .profile file and add the following:

export QT_STYLE_OVERRIDE=kvantum

export QT_QPA_PLATFORM=xcb;wayland

However, this can cause issues with some Flatpak applications, such as Telegram. I had to manually disable Wayland for Telegram using Flatseal; otherwise, the application would not start. Furthermore, I disabled the transparency effects for Qt applications through Kvantum.

Ideally, the default setup could provide a consistent Qt experience without requiring these manual configuration changes or causing compatibility issues with Flatpak applications.