unsure if this is known, but if not, glad to help

I found, on bosses with cutscenes you cant skip i.e. azdaha, if you switch just before (might be frame perfect) the cutscene starts, you can do actions, but the boss is invulnerable. like in co-op. is this useful? kinda. you could set up support bursts like Bennett, or get a Zhongli shield, or more I couldn't think of

link of example:

does this game support full screen, if so what button to turn it on