Hallo.
1 arrange and mixer view its saved window set F7 & F8
I need more information about "the window suddenly shifts to a different position."
2 for browser button you need scripts
1 Arc_Function_lua
2 Archie_Var; Show hide Media explorer FX browser Track manager Region-marker manager
when you run script 2 - opens 4 windows ,you need dock they all in left dock
Browser button its cycle action