Sometimes the windows decide they go into mosaic mode and they will share the whole screen, I cannot resize them or move them around, they just switch between themselves. Once it happens I found I can fix it doing "Float window" [Super F] but it's annoying the the windows decide to change behavior by themselves. Is there a function somewhere to keep the windows from randomly going into mosaic mode?

Can you post a screenshot? I guess you're referring to window tiling, do you have it enabled in System Settings?

doubtful but do you have tiling enabled? systemsettings -> windows behavior -> window behavior -> enable tiling ?

version of KDE?

is this a recent occurrence ? recent install? recent upgrade?

is you create a new user does it also experience this?

Thanks, it was that, indeed. I didn't find this when I looked first.