Extensions for Microsoft Edge will be coming soon via an updated build of Windows 10. It appears that Microsoft plans to distribute the extensions (plugins) and add-ons using the Windows Store just like it does with regular Universal apps. 
The first Microsoft Edge extension has already been spotted in the Windows Store, according to Neowin.
The “Page Analyzer” extension, created by Vorlon.js, is already available in the Windows Store. It looks like a Windows 10 app, but behaves differently. Once the user installs it, it adds an entry to the Start menu and registers as a regular app. However, when you try to run it, it opens the Edge browser and starts in the browser.
The Page Analyzer extension seems to be created for web developers. It allows them to test their website performance and compatibility with Edge.
Microsoft Edge extensions are expected to be added to the upcoming Insider build. Rumors suggest that the extensions are already being tested internally by the company and are almost ready to be released to the public.
