Unable to delete posts even within Edit Message timeframe

Is it just me or is it a global change that one can't delete posts that one has made?

Earlier (till about two weeks ago), one could delete one's own post from within the Edit message window, thus allowing one to delete the message within fifteen minutes of posting. That option seems to have been disabled.

Is it possible for it to be restored?

The time limit for deletion is "5 minutes", and has been so by default ever since the phpBB software was upgraded in 2013.