If you access a website that has both Flash and HTML5, the browser will opt for the latter. But if the page requires Flash to work, then a prompt will pop up asking if you'd like to switch it on. You can choose to active it just for that session or to keep it on for that URL forever. If you'll recall, Microsoft and Google have been distancing themselves from Flash for quite some time, as well. Edge only displays Flash if it's a central element on the page you're looking at (say, a game or a video), while Chrome has started blocking Flash ads late last year.
On the mobile side of things, Apple has announced at WWDC that it's requiring all iOS apps to connect to the internet via HTTPS by January 1st, 2017. That means developers have to switch on a feature Cupertino launched with iOS 9 called App Transport Security. ATS forces apps to use a secure connection to help keep your data safe.
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