Rated 2 out of 5 stars
Although a clever solution for numbering, essentially ALL this does is number the tabs 1-8.
Alt + [1-8] does not work, only Ctrl. Only numbers 1-8. Would be better to number ALL tabs (like NumExt add-on), then use Ctrl +  for tab 9 and Alt+ [0-9] for tab 10 to 19.
To get to 20 and beyond, maybe use a solution like NumExt Addon where you have a field in status bar where you can type in the tab number.
Would be very nice if this add-on was extended.