I found the flag to disable it, but I’m really curious why the decision was made in the first place. On Chrome and Firefox, l If you double click this example HTML5 : https://www.w3schools.com/html/html5_video.asp, it will go full screen. I’ve always wondered why sometimes click on a video would make it go fullscreen, it’s laggy and annoying for me, even on high-end laptops. On My Mac, as well as in Windows and Fedora VMs.
This is a pretty dumb question - I would always expect a double-click to fullscreen, and a single click to pause/play on any video in any video player.
The decision was probably made many years ago for the very simple reason that clicking specific targets is much more difficult, so enabling people to use scroll wheel and mouse buttons to do things is a very efficient method of control.