Here is a summary of the changes I made for the support of minimal on Youtube:
There is a main execution function that is triggering each treatment function (force theater and hide live chat). This function is called each time the Youtube status bar is loading.
I added a hideLiveChat function in order to detect each time there is a chatframe section on the Youtube page. If there is a chatframe, the function will hide the live chat section and replace it with the dedicated button. This function will center the comment section if there is no chatframe.