I cannot figure this out; the block is not behaving at all like I expect it to according to the code. Passing over to Chris.

I am referring to the actual (side) block, not the bottom panel. Sorry for the confusion.

Noted. I'll look into it, however the bottom block also has problems. I'll split this off into two issues, this for the side block and the new one for the bottom one.

Okay, thanks.

Automated response: Users online block does not show Display name

The side_users_online block uses usernames (cached from the sessions table) instead of display names. Ideally, it should use display names. This will have a tiny performance hit as we need to query for the display name. But considering blocks have a cache, this shouldn't be a problem.

Needs checking if the bug exists in v11