Hey, thanks for the report. This is a known bug in versions 2.4.12 to 2.4.14. The extension host crashes and makes Cursor unusable. The team is aware.
Temporary workaround: roll back to the previous stable 2.3.x version.
Option 1 (via settings, if you can open Cursor):
Cursor Settings > Beta > switch from Early Access or Nightly back to Default
Option 2 (manual downgrade):
Download 2.3.x directly from Download · Cursor
More details and other affected users are here: Unable to access any extensions in version 2.4.12
After installing 2.3.x, everything should work again.