What do the symbols next to usernames mean on Lemmy? - eviltoast

I’m using Jerboa and I sometimes see symbols next to peoples’ username. One looks like a “no message” symbol, and the other looks like a “no person” symbol in red. What do they mean? Are there more symbols?

I’ve tried a web search but I only found results related to Motorhead and some kind of desert rodent.

Also, is it possible to search the content of posts on Lemmy? At least in Jerboa the search function seems to be only to search for communities by name. Surely someone has asked this before but I couldn’t figure out how to search posts.

Thanks!

Edit: added an example of the “no person” icon