It used to, but I haven't used that for a long time. Maybe it was changed?
I can't test at the moment. I'm watching tv and the numbers just change the channel in TV.
It still works.
But it works like hh:mm.
So if you enter 12:30 it will jump at point 12hours and 30 minutes.
I think your file is not 12hours long and therefore nothing happens.
You will need to enter 00:12.
Seconds can't be entered right now.