It suddenly worked after i restarted Epic Launcher(unintentionally, by rebooting PC).
And then second thing i noticed which just blowed my mind, so confusing:
Editor Preferences are not Editor Preferences actually, that is project-like attached settings. Meaning it does not save whatever i setup for IDE itself, which is some kind of nonsense.
After some research i got the situation: Let's FINALLY fix Editor Preferences in UE5 - #10 by midgunner66
Glad that i found out that at the early stage, when i just started using Unreal Engine. Just don’t adjust any settings, keep everything as default, since none of that will be saved anywhere.