I don't know if this a bug or if I just can't find the right setting to change this... When I maximize any app window using a keyboard shortcut the window isn't maximized. It has a gap around the "maximized" window (image 1 below) and when I double-click the app toolbar it maximizes fully (image 2). I'm on M1 Macbook running MacOS Sequoia 15.0.1 (24A348) with BTT 4.77.
have a look here
Thank you so much! Sorry I didn't find that thread originally. Problem solved.