Firefox Updates change the way Firefox loads, which means I have to reorganize my screen every day. Updates used to reload windows (ie, collections of tabs on the same project) in the same place, proportions, and size as they were when Firefox was closed. Now Firefox chooses, randomly relative to my workflow, where and how to place windows. If I have any say in the matter, I haven't been informed about it. I've stopped accepting Updates because of this, unless I know the Update includes Security issues or fixes Bugs that are at all relevant to my work.
Which means you're making extra unproductive work for me when you don't put the number of the Update in your popups saying that an Update is available.
