As a Roblox developer, it is currently impossible to truly fullscreen tabs moved out of Roblox Studio.
I use two monitors, one for scripting and the other to display the workspace/game. Sadly there isn’t an option to fullscreen the separate window, so I have to resort to making it look like it’s fullscreen.
Note: The picture below is obviously not almost fullscreen, but shows you a reason as to why this would be tedious.
Not only that but when I try to live stream with this setup, the resolution is off, so it won’t display correctly on stream. You will see black bars, which is not good.
This also applies to coding displays, not just the game display.
It also really sucks that I have to try to get this to fullscreen each time because Roblox Studio does not save the windows’ sizes/positions (so maybe that could be a feature as well?)
It would be really awesome if this feature could be implemented, and if it already is and I just don’t know about it, please let me know! 
