Allow to set my own intervals in the focus timer

Great Idea with that timer, but I work in another focus time system. Can you make this clock changeable? I would love to have an opportunity to make this scheme 50 min. focus/ 10 min. rest/ 50 min. focus/ 20 min rest etc.
Now for this purpuse i use this one https://addons.mozilla.org/pl/firefox/addon/simple...
but it would be nice to use it n your apps