For the tbtw campaign i done that extension: https://github.com/Mte90/how-many-resources
The purpose is to show how many external resources a page load, so we can mobilize about privacy and development.
The code is commented so much and the way to use it is very simple, there is a button that inject an iframe with another button. That button show that informations in the iframe and there is a background script that communicate between the browser (to inject the iframe), a content script for the page for the iframe and the iframe content.
For the tbtw campaign i done that extension: https://github.com/Mte90/how-many-resources The purpose is to show how many external resources a page load, so we can mobilize about privacy and development. The code is commented so much and the way to use it is very simple, there is a button that inject an iframe with another button. That button show that informations in the iframe and there is a background script that communicate between the browser (to inject the iframe), a content script for the page for the iframe and the iframe content.