@kklo Did you resolve this, I am getting the same error. When running regenerate files for the first time, it got about 2% through then said:
<p>There has been a critical error on this website.</p><p>Learn more about troubleshooting WordPress.</p>
In the dev tools it has an error here: https://example.com/wp-json/webp-converter/v1/regenerate?_wpnonce=3ab0bc7622
this url leads to a page that just has:
{“code”:”rest_invalid_param”,”message”:”Invalid parameter(s): paths”,”data”:{“status”:400,”params”:{“paths”:”Invalid parameter.”},”details”:[]}}
