KDE better supported than Gnome for GUI scaling?

### System Information

Ubuntu LTS 24.04 w/ Gnome

### LMMS Version(s)

1.2.2

### Most Recent Working Version

_No response_

### Bug Summary

Hi everyone,

My laptop screen is a high resolution screen (about 2500x1600) and when I installed LMMS (Ubuntu LTS w/ its default desktop environment) the UI was too small for it to be used.

As I also got other minor issues on this system (related to my microphone, + I wasn't a big fan of some aspect of Gnome), I decided to distro hop to Kubuntu LTS 24.04.

So I installed LMMS on this new system and I was pleased to find out that the UI was correctly scaled this time.

TL;DR: It seems that KDE is better supported by LMMS 1.2.2 than Gnome when it comes to GUI scale detection.

If it's technically possible, implementing a setting to manually change the UI scale would help when people are experiencing this kind of issue.
I heard that there is a trick to do it by tweaking a setting in a config file somewhere, but it might discourage some users to stick with LMMS once they got through the settings and didn't find out a way to scale the UI through a user interface.

I tried to see if there already was an opened ticket on this kind of problem but it does not seem to be the case, please tell me if I missed one.

I'm willing to provide as much details as I can.

### Expected Behaviour

LMMS should be able to detect which scale the UI should use regardless of the desktop environment that's in use... Or provide a Graphical setting to scale it manually 😁

### Steps To Reproduce

Running LMMS on a gnome-based Linux distro (it was either Ubuntu 24.0.4.3 or 24.0.4.5) on a high resolution screen
I don't have any logs to provide you with as I already switched to a new system, but I could provide a hardware report if you think it could be helpful.

### Logs

_No response_

### Screenshots / Minimum Reproducible Project

_No response_

### Please search the issue tracker for existing bug reports before submitting your own.

- [x] I have searched all existing issues and confirmed that this is not a duplicate.

The report does not name source files, tests, or an entry point. Reproduce the scaling difference on Ubuntu GNOME and Kubuntu, then verify that LMMS detects the same high-DPI scale or exposes a usable manual setting.

Written by the indexing model from the issue text.