This addon is great for saving a webpage as a file you can open later, almost like a PDF. It's much more capable than Firefox's native "Save page as" feature. This is a good add on from my experiences using it. It's useful if you, for example, have a webpage with specs for a vehicle you are working on, and you want to save it for later in case the page gets deleted. With just a click, you can save the entire page as a file for later.