the option to show and hide the menu bar in full screen does not work with Firefox. However, this option works well with Safari and Google Chrome. I have macOS Monterey 12.4
I hope you can fix this issue in your next update. Thanks!
+1, can't check the time from the MacOS menu bar while watching a video (youtube, netflix, ...) in full screen, as hovering the mouse near the top edge of the screen does not drop the menu bar, I have to exit the video from full screen to check the time. This is not an issue while using other browsers (Google Chrome, Brave, ...), would be nice if the Mozilla Team could fix this issue. Thank you