Firefox does not save blocked sites.
In Tools, Options, Privacy, Exceptions, whenever I add a site to block, that site is later deleted. Not sure if this deletion is happening at shut down. Sometimes I notice a blocked site is deleted even before I shut down.
Wšě wotmołwy (1)
- Make sure that you do not use Delete browsing, search and download history on Firefox to clear the the "Site Preferences" as that will remove all exceptions and reset some other settings