This really sucks, he was doing a great job as a core contributor. I’m not going to speculate on the why since it looks like internal drama between him and the team, but what shocks me is how sudden he left. He just finished and merged a big PR to rework the project manager UI a day before this tweet.

Edit: The Godot Foundation just released a statement

It is true that the Foundation has parted ways with Yuri. Please respect that we as an organization will not go into further detail, we value protecting any former contractor’s privacy over public demands.

However, due to the rampant speculations out there we see the need to emphasize: This situation has nothing to do with Yuri being of Russian descent (a country he has not resided in since before our contracts). We always have and will continue to condemn personal attacks, on Yuri as well as anyone else we are working with.

Lastly, Yuri was one of many valuable contributors to the project, his absence will be felt. The core team is working hard to ensure that we can continue working efficiently.