I recently upgraded my JabRef to Version 5.0. Before the upgrade I could simply double click on a “.bib” file and it would open in JabRef without any problems (I have a file association for “.bib” files and JabRef). Since the upgrade, when I attempt to do the same, JabRef launches but gives me a “file not found” error. Sometimes if I close this error window my reference database still opens, but other times not. If I launch JabRef first, and then open the “.bib” file from within the program I do not get this error. Any advice would be appreciated.
I am afraid, I am not a developer myself (just an avid user that likes to do bug reports :D), so I do not know, what the official stance is. Having said this: Since you have reported the issue at Github as well, I reckon that is enough and this thread probably (?) can be marked as solved.