What is ProCon?
ProCon is a content filter for the Firefox browser created by Corvineum, and based on BlockXXX (by Tom Christensen). ProCon filters any type of content on any web page. If left on default, ProCon limits itself to filter pages containing explicit content automatically, based on the text. ProCon can also be used as a profanity filter, and makes use of a whitelist - useful for trusted sites.
Where can I get it?
ProCon can be freely downloaded from its Add-on page [link]. Once installed, you should be able to configure it according to your needs.
Where can I find help or more information?
All the documentation and help that you might possibly need are found here [link]. If you do need further explanations, not covered in that section, do not hesitate to contact me at the email provided within the same extension.