Using workers make trouble if i open two browsers

I have 2d canvas game also i have one video .

To fix bug with lost focus (i minimize browser or switch tab) i implement web workers script hackerTimer.

And it is better result with this script but my console frees in case two opened tabs with some game. Also frame rate (drawing) is too much slow.

Is it possible to avoid this situation.

Looks like workers are very good like new thread but looks like 'global' how to say. Maybe i can make edit in hackerTime script to make uniq instance of workers service? Maybe two pages share same resource...

Any suggestion ?

Please don't give a negative point without comment.