I don’t know what the cause of this is. However in-studio, in edit mode, my FPS is extremely low and developing games is relatively impossible. If I minimize the window, then return to it, the FPS boosts up and for a few minutes it is nice and smooth, but then the Frame rate drops significantly and I have to wait a little bit with the window minimized, then return to it and the problem is solved. However when playing ROBLOX games, or when editing a game in solo mode rather than edit mode, the game is always smooth. I don’t understand why this is so. Physics calculations are being made and scripts are running when there is a player in the game. If anything it should be more jumpy and slow. But no, instead, Edit mode is the only thing cursed by this saddening reality.
First thing I would recommend is to uninstall roblox, restart your computer then reinstall roblox and see if the problems persist.
Include the Place file for the Admins so they can have a look, and perhaps some of you specs. That way we can help you out 
I have the same issue.
IT also clears up when i look away from all blocks.
Like out into space
Test post
test post