https://support.torproject.org/tbb/maximized-torbrowser-window The gray
bars in Tor Browser when you resize/maximize it make you safer, not perfectly
safe. When browsing example.com with a window size of 1111x888 without
letterboxing, you are most likely the only one, thus unique. But when browsing
example.com with letterboxing, your window will appear to be 1100x800, which
**maybe** some other TB user visiting example.com will have too.
Assuming most people do not resize TB's window, for best anti-fingerprinting
results, leave TB's window size alone. Window size can be determined with CSS;
disabling JavaScript doesn't help: https://matt.traudt.xyz/p/YF4ciVY6.html.
No, having a common monitor size doesn't help: ask me about the FAQ
fullscreen-torbrowser. Letterboxing can be disabled with the about:config
option privacy.resistFingerprinting.letterboxing.
