(Fractional) scaling issues on KDE/Wayland

[major-mayer]

Description

DBeaver looks like this when launching it on my instance:

I am using KDE 5.27.11 and Wayland with fractional scaling set to 140% on a UHD display.
But even if I set the display scaling to 200%, so a non-fractional scaling value, the UI is very distorted, just that now everything is a bit larger.

Since this issue was closed because apparently DBeaver looks correct now on Gnome/ Wayland, I thought it might be time to open a new one specifically for KDE/ Wayland.

Workaround: Start DBeaver using XWayland GDK_BACKEND=x11 dbeaver.
The problem with this workaround is that no fractional scaling is supported for x11, so GDK_SCALE=1.4 wouldn't work (I think it's rounded to 1.0).
So all UI elements are very small on a HiDPI display.

DBeaver Version

Community Version 24.0.0.202403042157

Operating System

Manjaro Linux KDE/ Wayland

Database and driver

Not relevant

Steps to reproduce

1. Set up a KDE Wayland session
2. Start DBeaver
3. Notice the numerous UI glitches

Additional context

Operating System: Manjaro Linux
KDE Plasma Version: 5.27.11
KDE Frameworks Version: 5.115.0
Qt Version: 5.15.12
Kernel Version: 6.6.26-1-MANJARO (64-bit)
Graphics Platform: Wayland
Processors: 6 × Intel® Core™ i5-8600K CPU @ 3.60GHz
Memory: 31.3 GiB of RAM
Graphics Processor: AMD Radeon RX 6800
Manufacturer: Micro-Star International Co., Ltd.
Product Name: MS-7B46
System Version: 1.0

[anaximeno]

I also noticed the same issue while testing Fedora KDE 40 which was released with the new KDE Plasma 6. Also if you have multi-monitors with different scales it will ask you to restart the app every time you move the dbeaver window to another display.