Download, unzip, and run BrowserAddonsView to display the browser addons and plugins (i.e. extensions) that have been installed on your system. I ran this on my PC and it quickly (lightning speed) picked up every single extension I had installed. I can see this being used to troubleshoot issues where a rogue browser extension (or plugin) has been installed and has compromised the operation of your computer, your privacy, and your security.
BrowserAddonsView is a simple tool (by NirSoft) that displays the details of all Web browser addons/plugins installed in your system. BrowserAddonsView can scan and detect the addons of most popular Web browsers: Chrome, Firefox, and Internet Explorer. For Chrome and Firefox, BrowserAddonsView detects and scans all Web browser profiles if there are multiple profiles.