app.update.auto is getting changed to true
We currently ship a prefs.js in TBB that disallows auto updating of Firefox, but for some reason this is being changed from false to true, either at run time or some other time. I think it is possible (likely) that either one of the other prefs for updating we set to true is causing this other one to be overridden, or we are missing some kind of build option (or adding one inadvertently) that is causing Firefox itself to override/overwrite this pref. I will investigate and fix this before our September 10th release.