MacOS: application window keeps closing in the background

I agree. Often when we have situations like this it is helpful to see some of the users normal work patterns. It might reveal an app running that may be closing things. It may be that we notice an extra step that you miss or we miss when trying to reproduce a behavior. I have been guilty of providing steps and then you get into the groove and you accidentally forget one small step and that ends up being the key to unlocking the whole situation. There's no guarantee something like that will happen here but it might be the best shot we have to go off of. I can't count how many time a video has helped. I'm hoping it might. Just maybe.