How Flash works with Safari 11 in macOS High SierraEven though it's off by default, you can still use the Flash plug-in in Safari on macOS High Sierra. Here's how.
While sites and services continually adopt newer technologies such as HTML5 in the place of Flash and other older plug-ins, in your internet activity you'll likely find that Flash is still a major component of a number of sites. Some browsers still treat these plug-ins the same as they always have, but Safari has a different way of interacting with Flash than it has in the past.
For one thing, Flash is off by default.
How Flash works in Safari on macOS High Sierra
Since macOS Sierra, Adobe's Flash plug-in has been turned off in Safari by default to encourage users — and websites — to use HTML5 for features like video, and this remains true in macOS High Sierra. This is because Flash is easily exploitable, and if someone with nefarious intentions hacks the plug-in or the site, Apple previously couldn't prevent users from being exposed.
However, ...
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How Flash works with Safari 11 in macOS High Sierra
