Unfortunately, since January 2017, Stylish has been augmented with bonus spyware that records every single website that I and its 2 million other users visit. Stylish sends our complete browsing activity back to its servers, together with a unique identifier. This allows it’s new owner, SimilarWeb, to connect all of an individual’s actions into a single profile. And for users like me who have created a Stylish account on userstyles.org, this unique identifier can easily be linked to a login cookie. This means that not only does SimilarWeb own a copy of our complete browsing histories, they also own enough other data to theoretically tie these histories to email addresses and real-world identities.
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If you use and like Stylish, please uninstall it and switch to an alternative like Stylus, an offshoot from the good old version of Stylish that works in much the same way, minus the spyware.
“Stylish” browser extension steals all your internet history | Robert Heaton
fair--y backup 