comment télécharger avast anti track sur firefox merci?
Hey @Gratienne_Dell_Omo! Welcome to the Add-ons section of Mozilla’s Discourse server 
There are a variety of reasons that an add-on may not be available on addons.mozilla.org. In my experience, the two most common reasons are:
- the developer removed the add-on (or all public versions of it)
- Mozilla removed the add-on (or all public versions of it) due to a violation of the Add-ons Policies.
Your best course of action is to look for information on the developer’s support website or community forums.