The user card is what pops up when you click on a username on a post (or an @mention, eg @ian_chimp). And then if you click on the username in that it will take you to the profile page proper (eg. https://lovehoneyforum.com/u/ian_chimp/summary)
Yeah, Discourse [1] has a lot of features and if you’re not the ‘click every button and see what happens’ type then it’s easy to miss some useful bits. To be honest, even if you are a ‘click everything’ person then it’s still easy to miss some. 
They add new stuff all the time (like the [grid] tag for displaying images) so there’s often an extra treasure to find even when you think you already know everything.
There are a few basic tips in the How To, and the Discobot Tutorials can help with some others, but I think most people here are generally happy keeping it simple and don’t use a lot of the bells and whistles.
But if you ever come across something you think should exist but can’t find, or want to do something and aren’t sure how or if it’s possible, then you can send out a bat signal in The Sandbox and I’ll try and help as best I can. 
this particular forum software ↩︎