The addon is Better Fishing. It allows the use of a hotkey to cast, same hotkey to interact with bobber, and then you’d rinse and repeat.
I saw a streamer recommend it, and it has like 1.1m downloads on CurseForge. I’d hate to use it, and find out it’s not allowed. I got way too much stuff to lose, so I dare not use it
I don’t think there is any problem with using this addon, it’s an official addon on Curse which gives you no advantage over other players.
Nice to know there is a fishing addon like this, I think I will get it myself!
I don’t use an AddOn and can use 2 keys to fish. One casts (via a macro) then Interact (F key) to reel in the loot.
If only I could macro /interact into a cast sequence (I did play around with macros to do this for a wee while to no avail but I’m no expert on macros) then I could do it in one key.