If scaling is off, there's a good chance the application is using GTK. GTK4 doesn't support fractional scaling but I believe GTK5 might.
If applications are written in GTK2/3/4, fractional scaling won't work well and lead to blurry windows.
Integer scaling (1x, 2x, 4x) should work just fine, but fractional scaling isn't implemented consistently across GUI frameworks. Hopefully Wayland will fix the inconsistencies between implementations, though GTK and some other GUI frameworks will likely remain broken for a while.
If applications are written in GTK2/3/4, fractional scaling won't work well and lead to blurry windows.
Integer scaling (1x, 2x, 4x) should work just fine, but fractional scaling isn't implemented consistently across GUI frameworks. Hopefully Wayland will fix the inconsistencies between implementations, though GTK and some other GUI frameworks will likely remain broken for a while.