Circuit display shows bridge as *middle* hop?

pastly points us to a recent reddit thread, where somebody has a screenshot of their Tor Browser circuit display, where the middle hop is labeled simply "bridge":
https://old.reddit.com/r/TOR/comments/kt5fkl/i_got_a_bridge_as_my_middle_node_is_this_normal/

My first theory is that Tor Browser (Torbutton? Tor Launcher?) is doing a lookup, failing to find something, and has logic to say the word 'bridge' when the lookup fails.

That is, it seems much more likely that the labeling is wrong than that Tor somehow stuck a bridge in the middle hop.