Author changes popular VSCode Material Theme license, threatens to sue

The threats about suing was some drama that happened back in the end of December last year.

The link you posted is to a fork by a guy who made a video about it back then.

https://www.youtube.com/watch?v=3wz7YF2as-c

It's 15 minutes long. Basically, the original theme author was threatening to sue people, even though he had released his project under the Apache License 2.0.