Thank you Tobias.
Yeah, Mac can be a bit of a problem sometimes. In any case, I’m happy I could solve this problem. JabRef is much superior to other managers. I do have one issue that it could be fixed and one suggestion. The issue is copy and paste: whatever text I paste into JabRef (all fields but BibTex source, including WebSearch), it writes it down twice. So “Tobias” appears “TobiasTobias”. As for the suggestion, it would be very useful to have a DOI search in WebSearch. But mind you not through crossref or others, but rather something like doi.org does.
Anyways, thanks for the hard work!