A user has managed to reveal a bug by choosing a BOINC displayname/username that is causing problems. I found this bug when I noticed there was a row in the einstein user moderation queue that is empty. The source-code points to user: https://einsteinathome.org/account/125248, which has no username- it is displayed as blank. On the user edit page (admin only), one can see his name is
This is the same text I see in the BOINC database. But for whatever reason Drupal cannot render it.
There seems to be some special character that is breaking something somewhere.
Update/Summary: If you see this behavior, look at the source-code of the page. You will be able to find the link to the user's account page in which will tell you what user (Drupal ID and BOINC ID) is causing the problem.