The new UWP launcher app won't open sometimes (It won't even get to the login screen before it crashes), I've known about this for a while, but I thought it's been fixed already.
Edit: It always happens when I play on any launcher that isn't the UWP version (either the Old Launcher or Lunar Client, my multiplayer client). It's fixed when my PC restarted, so that's why it's fixed when Windows Updates.