Edit thread titles

[Mooncat]

Forgive me if I'm being dumb, but how to I edit the title of a thread I've already posted? I have a thread I use for guitar lessons and I'd like to just use the one thread and update the title of it with each new post but I can't see how to do it. I've done it before but can't seem to anymore. Did that feature change? Or am I just being dumb?
Thanks!

[DeletedUsermNqGIiIuGy]

Click on the modify button on the right side. There's modify and modify inline

Its the 2nd icon. square with a pen in it

If you just click the pen icon (3rd) you'll only be modifying the main text

[Mooncat]

Ah excellent, thank you!