So, Late morning, you're in a hurry, doing many things all together full of stress, your boss is mad and you really need to open Firefox as fast as light but instead of this, a pop-up comes out saying:
"An update ongoing, please wait and Firefox will open later"
OMG! This is so much annoying! I mean, ok, updates are important but when you are in a hurry this pop-up cause you psychotic and stressful feelings!!! I have disabled Auto-update to all my work PC's just for that reason
Why not users being able to Postpone update for the next time Firefox will load or even better the option "Do the update after closing Firefox" or "Ask Next time"
I think this is a very good suggestion if you are so much busy all the time like I am!