How to restore legacy QuickTime 7 web plug-ins on MacIt might not be common, but sometimes you need an old plug-in, even in this day and age.
While many sites have made the transition to HTML5 for video on the web, you may run into a site that requires older plug-ins such as the QuickTime 7 web plug-in in order to play some videos. While that plug-in has not been enabled by default since OS X 10.9 Mavericks, you can still enable it if you need to.
How to restore the QuickTime 7 web plug-in on your Mac
The good news is that enabling the plug-in isn't difficult. Unfortunately, it's also not intuitive.
Click Go in the Menu Bar while in Finder.
Click Go to Folder.
Type /Library/Internet Plug-ins in the search field.
Click Go.
Hold down the Command key (⌘) and double-click the Disabled Plug-ins folder. This will open the folder in a new tab.
Drag the QuickTime Plugin.plugin and nslQTScriptablePlugin.xpt files from the Disabled Plug-Ins folder to the Internet Plug-ins folder.
Enter the Administrator username and passwor...
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How to restore legacy QuickTime 7 web plug-ins on Mac