Letterboxing on Tor Browser for Desktop

Tor browser content isn’t rendering over the full screen. Rather, it looks like its running on a VM :smiley:
Is it going to be this way forever?

This is not a bug but a feature known as Letterboxing. It works by adding margins to a browser window so that the window is as close as possible to the desired size while users are still in a couple of screen size buckets that prevent singling them out with the help of screen dimensions. In simple words, this technique makes groups of users of certain screen sizes and this makes it harder to single out users on basis of screen size, as many users will have same screen size.


So what is the recommended window size? Leave it the way Tor Browser opens or is going full screen on a normal sized display still okay?

ref. What are grey bars on resized Tor Browser window? | Tor Project | Support

Tor Browser in its default mode is starting with a content window rounded to a multiple of 200px x 100px to prevent fingerprinting the screen dimensions. The strategy here is to put all users in a couple of buckets to make it harder to single them out.

The default window size is recommended.

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