Keep maximized right panel state when toggling it

[fxposter]

Right now if you open right panel, click maximize it, close it and then open it again - it loses the maximized state. Can we instead open it in maximized state directly in this case (ie: save the maximized flag instead of clearing it out on each toggle).

[xixixao]

Adding more context:

Problem: I want to switch between conversation and full-screen Diff. But right now that's not possible, I can only assign a shortcut to maximize/minimize.

Potential solution: If the maximization stayed sticky after toggling, I could just toggle the right panel on and off.