Tested that it fails on main reproducing the issue:

```
    - Expected  - 0
    + Received  + 8

      from time import sleep
      input()
      print('before sleep')
      sleep(0.1)
      print('after sleep')
    +
    +
    + x
    +
    +
    +
    +
    +
```

https://bugzilla.mozilla.org/show_bug.cgi?id=1867893

`:has()` is not only not yet officially supported but is hard to
implement well so no wonder there are difficult invalidation bugs