This is a GREAT addon. It is easy to use - just click icon in addon bar and it converts tab to a pdf, which you can open in your pdf viewer or save to disk.
The only caveats are:
2- Good and bad : this program converts to a pdf with a good 'zoom' percent - pictures and font are easily readable. However, in some cases, this results in a single webpage converting to a 40pg pdf!
The above issues are easily addressed. I have downloaded this addon and I use it regularly.
On the rare occasion I have had an issue it has related to the two above-mentioned caveats - in such instances this is easily addressed by using the "print pages to pdf" addon. It converts to a pdf file w/smaller font.
-I use both apps because this one is FAR easier to use - 1 click operation.
-the other takes a bit more time to convert and a bit more work, and it often hangs when converting and freezes. I thus use it infrequently and only as necessary.
This pdf addon is my primary, and favourite addon for this purpose.