Will this lead to easier fingerprinting?
this post was submitted on 01 Apr 2026
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The short answer would be probably not. Tor browser uses dark mode by default, and since this is also a dark (mode) theme that doesn’t change. It only affects the chrome of the browser, not the pages themselves.
The longer answer is that in theory it may be possible to use some kind of exploit or side-channel attack to figure out what theme is enabled or which themes are available through media queries for example with JavaScript or CSS.
So that is something you should keep in mind for your threat model.
My answer is based on personal experience, some basic googling and asking the Tor community. But it still can’t hurt to do some additional research yourself. 😄
Feel free to correct me if I’m wrong.
My first thought is: anonymity is all about entropy
Do as little as possible to be distinguishable from other Random Tor User, to any sites or services you interact with.
As long as it's just a client side theme that swaps out colors on device, it shouldn't be able to be used for fingerprinting, right?
right. the only concern there would have been altering the size of the viewport, but that hasn't been relevant ever since they added letterboxing
theme it however you like
Yep. While it seems to be the same just the client side theme, on Tor browser I never take a chance with modifications.
Garlic theme would be cool
People still use fedtor?