Browser Add-on to screenshot a whole page.

I watched this video: [https://youtu.be/gue5MofILxY?t=2354](https://youtu.be/gue5MofILxY?t=2354) and Cody Kinsey mentions a browser add-on that can continually scroll to the bottom of someone's social media feed or website and screenshot all the way down. Later this tool stitches these together as a pdf to keep a record of their page. Is anyone familiar with a tool or browser add-on capable of this? The tools I've found are either not free or don't work.

browser computerforensics screenshot