Kicked to a login screen at launch

I'm hitting a bug where I log into my account, go to the game I'm DMing, launch the game and then it kicks me back to another login screen. From there any attempt to log in just returns to that login screen. Please help! I'm running a game on Friday and have maps to build.

It looks like clearing my cache fixed this. But I've had to do that an awful lot lately for crashes in Roll20. What's made the platform so unstable lately?

If you look around the forum for the last few days of posts, it shows that Roll20 has been undergoing some unexplained loss of service, likely due to forces beyond their control for the past couple of days. If you go back further than that, there will likely always be periodic issues with a web based service. Roll20 is a complicated web site that depends on their own service providers (Cloudflare, Amazon Web Services, and probably a lot more) that all also have to be functioning correctly.