This one is a joke! It uses an unknown third party server to make the PDF, and if the page you are trying to convert requires login, you get just the login prompt in the generated PDF.

PDF Saver is a really solid and practical Firefox add-on. It makes saving web pages as PDFs super quick with just one click, which is exactly what I needed for work and reading. The interface is simple and clean, and everything feels smooth without slowing down the browser. It handles pages reliably and produces clean PDF files that are easy to store or share. For anyone who needs to archive pages or keep offline copies, this is a very useful 5-star extension.

As much as I wanted to like it, I can't. It doesn't save what you see, rather tries to grab the page using external services - for paywalled content it simply does not cut it.
What's more: adding a footer to every page marking that it was captured using this plugin, is yet another bad move.

requires some server and doesn't work offnline.

A great app, thank!