I do not use auto rotate to switch to landscape format but the manual rotate button which shows up when you disable auto rotate. When i play a video in the Firefox Browser on Android and rotate with the button it rotates to landscape. When I then play a video (for example on youtube, but not only there) and open it in fullscreen and go out off fullscreen and want to rotate back to portrait the button just does not appear and i am stuck in portait format. I need to close Firefox and start it again for it to work properly again.

I hope I am right in asking for help here since this problem does not occur with Chrome but if I am wrong please tell me where to ask for help.