I had the same problem on lemm.ee when that admin upgraded it. In my case, it only happened when I was on Firefox on the desktop. It happened because I had Spanish installed as a display language.
If you have more languages than just English installed in the browser, remove them, close the browser, re-open the browser and see if it works. @https://lemmy.world/u/ruud, If you see this, ask @https://lemm.ee/u/sunaurus what he did to fix the issue on the backend.
I did a write-up on what I tried. My username is the same on lemmy.world as it is on lemm.ee.
Thanks! That will make communities ear to find.