If you search for Avast or AVG companies on the official Mozilla Add-ons website, you may notice that they will not return results. Neither Avast Online Security nor SafePrice, nor AVG Online Security or SafePrice will appear.
Mozilla seems to have removed these extensions from its Store. So when you try to open one of the Avast or AVG Extensions URLs, an error message is displayed “Oops! We can not find the page ".
Extensions are however not included in the black list by Mozilla. Blacklist extensions are removed from users' browsers.
The extensions of Avast and AVG seem to have been removed but not excluded, meaning that the extensions remain installed and enabled in Firefox for the time being.
Mozilla added several dozen Firefox extensions to the blacklist on December 2, which collected user data without their consent, but Avast extensions were not included in that list.
Wladimir Palant, developer of AdBlock Plus, he published an analysis of Avast's late October 2018 extensions on his personal website. It found that the Avast extension transmitted data to Avast, which provided the company with information from its browsing history. The data sent by the extension was not necessary for Palant to operate the extension.
Mozilla appears to be in talks with Avast, according to Wladimir Palant. It is possible that Mozilla will add the extensions to its blacklist or ask Avast to make changes to the extensions before resetting them.
Extensions are still available for Google Chrome until now.