To begin with, it is probably released with a subset of the CI matrix, because I imagine that the full CI matrix takes more than a day. Second, it is nearly im

To begin with, it is probably released with a subset of the CI matrix, because I imagine that the full CI matrix takes more than a day. Second, it is nearly impossible* to cover all possible environments+addons+websites and test them correctly. This isn't a normal desktop app, nor a webapp that always is running relatively sandboxed in a more or less known environment. Browsers are platforms, as OS are. Lots of people doing wacky stuff on it. Very hard to realistically automate all that stuff. *impossible with a limited constraint of time and/or money.