Hello, I’m new to GNU/Linux. So, I don’t know many basic things. I’m using Plasma DE. I tried to make everything dark by applying themes from global theme setting, then from application style, I tried to make everything transparent and blur. But these dark themes and transparency effects does not works for everything including softwares (like CodeBlocks). I also tried Kvantum Manager to make everything dark and transparent, but failed to make it happen. I also followed some YouTube videos, but some of the settings options were different from my version.
If anyone wants to help a noob like me, then it will be really appreciated.
The plasma theme applies for the environment itself (settings, Panels, etc.) and for KDEs own software (like Konsole, Kate and such). There is also a certain range of compatibility with other software KDE has no control over, but if you use a program by Gnome for example, you run into trouble and your theme won’t be applied there.
For that, there is a toggle in the settings menu → Appearance → Application Style → Configure Gnome/GTK Application style.
Packages you install via Flatpak are another story since the whole point of it is, that a developer only has to deploy for one distribution and Flatpak manages the rest for other distros and installs important dependencies (I might be mistaken here). So if you want a consistent look throughout your desktop, you have to install stuff like Kvantum or Spicetify (for Spotify themes).
This whole thing becomes a mess really fast, and I think people on r/unixporn who write their own themes for everything on their desktop are pretty underrated.