There are plenty of content blockers available on the Firefox Add-ons Store, but uBlock Origin is the undisputable king in the category. They are safe to use and improve the browser significantly.

The following 10 extensions are regarded highly by the Firefox community. Selecting the three-dots menu displays an option to remove it completely from Firefox. Check the rating of the extension on Mozilla's website, and also read the linked privacy policy and other resources linked on the page. It is a good idea to read the description and user comments carefully. These permissions give them additional capabilities, and it is a good idea to check them to make sure that they only request permissions that match their functionality. Some extensions request extra permissions and Firefox users see a prompt during installation that lists all these extra permissions. Only these are tested manually, while all other extensions are scanned automatically only. Mozilla maintains a list of recommended extensions on the Add-ons Store, which are tested by the organization before they are published on the store. The vast majority of extensions are useful and safe. This does not happen very often, at least not on the Firefox add-ons store, but it has happened in the past. While the answer may not please everyone, the past has shown that extensions may be malicious and that they may be pushed to the Firefox extensions store or Google Chrome Store.

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