Of course there is a demo key and not asdf, just did not wanted to share it here
Thank you for the link. Snappdf seems to be the recommended pdf converter.
/var/www/invoiceninja/vendor/bin/snappdf download
gives me this error Chromium binary already downloaded. Provide --force to download again.
so I do it again with force and change PHANTOMJS_PDF_GENERATION=false
I think I either need to restart again or try docker the next time.