Originally for Chrome. Tested it on Firefox and works just fine.. Very useful if you happen to have interesting articles or web pages that you want as reference, or you simply want to have a copy of. This way you can view it offline..
To install drag this Save Page as PDF to your bookmarks bar.
* Also tried it on Opera and works fine..
To use in Opera.. Just copy the script and add it as a bookmark cause Opera don't permit drag and dropping bookmarks..