Page Performance Test от Francesco De Stefano

Measures the timing performance of any web page using Web APIs. You can immediately save the chart test result within your file system for a comparison with other subsequent tests.
=======
«I also invite you to install Performance Map, a new add-on that serves to measure the page's performance through a heatmap» - https://mzl.la/2vWZHMZ
=======
Video tutorial - https://youtu.be/u2o3nD_-9KQ
=======
== Installation ==
1. Click on add-on button in Firefox Web Store directly from your browser and install extension
2. Then click on the icon of the extension included in console web of your browser to get data

== Features ==

• Page Load Time for network, server and browser
• Accurate Chart and Load Time for each one of tests
• Button "Save Result" of test with date time

Release 3.0
- Click WebExtension icon to open popup and quickly view a website's site performance leveraging the Web Performance API (See the first screenshot)
======
Release 2.5.0
- Now you can active page performance test devtools of browser