I have done a test (On windows 11), I’ve left open roblox for about 5 minutes on the white screen, it loaded me into the game I was joining, Stepford County Railway. I see some laggy spots, considering it is a laggy game. Next game I tried, Murder Mystery 2, not a laggy game. Same issue, white screen. After a few Seconds (wow) it got me into the game. I tried a round, not laggy at all. Overall my conclusions, Keep the game on for a few minutes or seconds and it will get you in. Happy to help! Also edit, freezes a bit
Please, mark this as solved if worked!