Launching the game the first time there was this black popup, after much trial and error doing with alt-tab I managed to get it focussed properly and it was an accept cookies popup, only then I was able to accept and dismiss it.

After a few matches, I got a blackscreen where the victory team would display and I could do absolutelly nothing, had to alt+f4. The chat still displayed, at least for a bit, so it could be a game bug or server load issue for all I know.