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.
It block most of the bad sites and u can also add some website by ur own.
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This one has kids browser which you can enable and disable according to ur requirement.
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