Hmm not sure why it still updates. Trying to stick with a random build on Aurora (aka Developer Edition) channel is not really intended to be used this way. The Aurora and Nightly channel builds gets checkins almost every day so they get a new update each of those days. This means there can be issues until finished, fixed, reverted or even intentional. Release <. Beta (b#) < Aurora (a2 ) < Nightly (a1)