Here is how to clean install macOS High Sierra, Sierra or OS X on Mac. The plug-in integrates seamlessly and through a preference pane, gives you control. Click on the drop-down menus next to the names of currently-open sites in Safari. If you want to give your Mac a fresh restart, you can perform a clean install of Mac OS. Adobe Flash Player for Mac lets you access Flash content in Web sites when using browsers like OS Xs Safari. However, there are some sites and services, such as Hulu, Spotify, and Pandora, that require the use of Flash for video playback, music streaming, and more. Click on Adobe Flash Player under Plug-ins.