When having a board open I can see at the top right corner the members of this board with a little picture:

What is confusing for me: I seem to only see the members that I've actively invited to the board. But I cannot see users who are a member of the workspace (and can see this board, too).
In other words: There might be other users who can do everything in the board, but there is no "little picture" of them. Is this correct? And if yes, how could I show all the users who have got access to the board?