Strange squares instead of non-latin characters in `JabRef` user interface

Hello there.

I’ve been a long time user of JabRef and absolutely love it.

This isn’t really a request for help. I simply wanted to put out there a solution to a problem that others might have encountered.

Up until now I only used JabRef to manage citations in English. It worked perfectly well. Recently, I tried to use JabRef to manage citations in my native Hebrew. The user interface did not display Hebrew characters properly. They were replaced by strange squares.

The problem did not occur on Windows 10 and 11. I managed to reproduce it only on Linux in the following setting:

  • Arch Linux with KDE and the portable versions of JabRef 5.9, the portable versions.
  • A relatively old and somewhat poorly maintained installs of Ubuntu 20.04 and Kubuntu 20.04 with the portable versions of JabRef 5.9.

My immediate thought was that I have a locale or font problem. After wasting several hours trying to figure it out, it turned out to be a font issue. The solution turned out to be very simple. I downloaded and installed the Segoe UI font family from the following repository: Once installed, the issue was complete resolved.

I presume that in the absence of these fonts, whatever font was actually used by JabRef simply did not include the proper character set for Hebrew. I assume similar issues may occur in Arabic and other non-Latin languages.

Hopefully this message will save someone some googling in future.

Thank you for a wonderful piece of software!


Thank you for your research and your insights. I will mark this topic as solved :slight_smile: