Multi Digit Tab Switcher and Mover от Risetwozero

This extension works best if you have numbered tabs.
You can achieve this by using custom css on firefox like mine :) or use a browser that has it.

Explanation on delay:
if there is more than 10 tabs there will be some delay to go to tab 1 with alt+1, you can bypass this delay by pressing alt 0, alt+1.
Similarly, if you have more than 20 tabs, there will be some delay to go to tab 2.