How to remove white lines (frames) TOR?

Question

Browsers

With the latest update in the torus, white lines, if expanded to full screen. Most likely so that it was impossible to detect the size of the browser window.
How to remove these lines?

Answer 1

Yes, this is the so-called "Letterboxing" against fingerprinting. You can turn it off in about:config by setting the value of the privacy.resistFingerprinting.letterboxing parameter to False