Minimalist alexa rank extension for firefox.
Install Alexa Rank from Mozilla Add-ons page.
https://extensionworkshop.com/documentation/develop/getting-started-with-web-ext/
Test an extension in Firefox by cd'ing into your extensions’s root directory and entering:
web-ext run
Alternatively, if running web-ext in Docker, install and run the FirefoxDeveloperEdition. In about:debugging#/runtime/this-firefox load the extension's manifest file and click the Inspect button to open the console.