Never, EVER use a Microsoft browser as a reference for how things should work!
As far as Adobe is concerned, they stopped development of Flash on mobile and recommends switching to HTML5 video/audio so don't think Adobe is still head over heels about Flash.
This is not about how things should work, this is about how things are going to actually work for a number of desktop / laptop users, with Chrome and a Microsoft-supplied browser being the two top choices.
https://en.wikipedia.org/wiki/Usage_share_of_web_browsers