Mozilla has put the YouTube Unblocker add-on on its “blocklist”, as it has been discovered that it was changing users’ security settings and covertly downloading and installing an additional, malicious extension that injects ads in pages visited by users.
The popularity of YouTube Unblocker was due to it allowing users to view YouTube videos blocked in their country. The add-on used to be offered for download on the organization’s official portal for Firefox extensions and themes, but no more: [...]
The various comments in the discussion about the bug that has been started on Mozilla’s bug tracker a few days ago showed that the developers of YouTube Unblocker have been repeatedly trying to bundle it with adware through the years.
Continued: https://www.helpnetsecurity.com/2016/03/04/mozilla-blocks-youtube-unblocker-firefox-add-on-due-to-security-issues/
See:
Firefox Add-on YouTube Unblocker blocked by Mozilla
http://www.ghacks.net/2016/03/03/beware-firefox-add-on-youtube-unblocker-put-on-blocklist/

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