Without vitest-mock-extended:
https://stackblitz.com/edit/vitest-5820
With vitest-mock-extended:
https://stackblitz.com/edit/vitest-5820-megvgc

Workaround:
Use skipLibCheck: true in tsconfig.json, but this isn't great
Another developer from vitest issues showed me this https://arethetypeswrong.github.io/?p=vitest-mock-extended%402.0.0 which shows the packages has malformed module syntax.
Without
vitest-mock-extended:https://stackblitz.com/edit/vitest-5820
With
vitest-mock-extended:https://stackblitz.com/edit/vitest-5820-megvgc
Workaround:
Use
skipLibCheck: trueintsconfig.json, but this isn't greatAnother developer from
vitestissues showed me this https://arethetypeswrong.github.io/?p=vitest-mock-extended%402.0.0 which shows the packages has malformed module syntax.