Disable device sensors in Tor Browser
I meant to file this bug for a while now but failed so far. We should disable the sensor API as getting data via/about device sensors may be a fingerprinting vector with little gain in the desktop world at least. Mozilla has a pref for this (introduced by https://bugzilla.mozilla.org/show_bug.cgi?id=740473),
Thanks to totentanz for reporting and the commenter in https://blog.torproject.org/blog/tor-browser-408-released#comment-92426 for reminding.