Tab Size on GitHub

Description from extension meta

Make tab indented code more readable by forcing the tab size to 4 instead of 8

Image from store Tab Size on GitHub

Description from store See the website for more info.

(2016-05-25) Leeroy Ding: I wish there's an option to change it to 2.
(2016-02-25) Rinat Khaziev: I was about to delve into developing Chrome extensions but then I googled :) Good job, does exactly what it's supposed to do.
(2015-03-19) John Gardner: YES! Finally! Hard tabs for life!
(2015-03-10) Hans-Harald Glatt: Great!! Thanks a lot!!
(2015-01-22) Derek Jass: Simple and useful.
(2015-01-18) Cloudy Wolf: Really Nice Work!
(2014-08-28) musamad musamao the 4th: Awesome, I really hate how Github forces 8, was going to write an extension to do this; but found this.

(2016-10-17, v:1.1.2) Toby Mole: Other sites?
Is this coded to work specifically *only* for GitHub or will it work for other sites (e,g, GitLab installs)?

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