I have a question, again. I am currently using a MacOS Big Sur and whenever I play inside ROBLOX studios, the rendering in my games goes horrible!
Here is before I play inside ROBLOX Studio to test:
Open Roblox Studio, Open the File menu, and click on Settings, Click on OK to proceed, Click the Reset All Settings button, located at the lower-left of the pop-up window. Let me know if this helps or not but usually resetting all of the settings will fix it.