Is there a lightweight free utility that tracks the time spent on a specific program?

Question

Windows

Or maybe an AutoHotKey script to monitor the activity of a single program.
It is desirable that information can be found from the tray, similar to the MemInfo

upd program:

It is important to add that it is advisable to calculate exactly the interaction, and not the time from the moment the program was launched and it was idle.

Answer 1

Maybe it's Motivate Clock
On Habré , the article is really old already.

Answer 2

The time of your interaction with the program?
ManicTime