Firefox Custom CSS Per Site

On a Mac go to your home directory then browse to:

“/Library/Application Support/Firefox/Profiles/sdfjdsf.default/chrome/”

sdfjdsf.default This folder has a random name

In this directory you need to create a new file:


Place any CSS in this file and it will be applied to any website you visit, a common use of this is:

add the line:

Hides the Facebook Advert Pane. Can also be used to hide any element.


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