You can find this tab on the left sidebar in the forums, at the bottom, along with your threads, subscriptions, and forum search. Here's a link :)
I've been losing the threads that i post and thought maybe it'd be a good idea to have like a thread post history on people's profiles so you can easily find back whatever you or other people have posted in the forums. It's a thing on other forums and i have been kind of missing it here! Hope you can do something with this in the future :)