User Agent: Mozilla/5.0 (Windows NT 6.1; WOW64; rv:38.0) Gecko/20100101 Firefox/38.0 Build ID: 20150129030202 Steps to reproduce: 1. Go to https://developer.mozilla.org/en-US/demos/detail/bananabread 2. Start any Map Actual results: On the nightly builds of Firefox, the pointer lock is broken and the sensitivity is set to godlike levels. Turning system and game sensitivity down, helps, but is still unplayable. Expected results: 35.0.1 - Good 37.0a2 (2015-01-29) aurora - good 38.0a1 (2015-01-29) Nightly - BAD With this I ran a mozregression --good 2014-9-20 --bad 2014-11-20 MainThread Bisector INFO Got as far as we can go bisecting nightli es... MainThread Bisector INFO Last good revision: 2114ef80f6ae MainThread Bisector INFO First bad revision: b62ccf3228ba MainThread Bisector INFO Pushlog: https://hg.mozilla.org/mozilla-central/pushloghtml?fromchange=2114ef80f6ae&tocha nge=b62ccf3228ba From this, https://hg.mozilla.org/mozilla-central/rev/b1e482f69d96 looks to be a likely cause of the regression.

Note that if the Jan 29 aurora build is good but Jan 29 nightly is bad then it's quite likely that the regression is recent (after Jan 12th) so the regression range of Nov 7th seems suspect. Also the changeset of mine that you identified should not have caused anything like this; I'm not sure what reasoning you used to pick that one out of the range.

Confirmed in 38.0a1 (2015-02-02) Win 7

This sounds like bug 1085567 - pointer lock is broken on e10s, which is only on by default on nightly. If that's the case, you should see things working ok when you open a non-e10s window.

Good call Alon. Yes, disabling e10s resolves the PointerLock/Sensitivity issue. I've closed this issue.