Extension causes webpage to be "laggy" and occasionally freeze

[fireattack]

This extension seems to cause webpage to constantly freeze or feels "laggy" from time to time.
It is most obvious when you just opened a new page.

It is also more obvious if you are using a "heavy" profile compared to a brand new one (I tested both cases, it is very noticable on my main profile (with all other extensions disabled), but not so much on a brand new one).

STR:

1. Open any long webpage. I use https://en.wikipedia.org/wiki/December_12 to test.
2. Once the page loaded, immediately start to scroll to bottom using single middle click then move cursor down.

What should happen: you can scroll quickly without pause.

What actually happened: when scrolling, it will pause for about 0.x seconds during the scrolling.

[fireattack]

This screencap shows the bug.

Video: https://files.catbox.moe/a1eypc.mp4
GIF version (less noticeable because of low fps and resolution):

Please notice the pause when scrolling, it happens everytime (I showed twice here) I refresh the page.