Firefox doesn't block autoplay

Hello Allow or block media autoplay in Firefox https://support.mozilla.org/en-US/kb/block-autoplay 1 - Go to configuration editor https://support.mozilla.org/en-US/kb/about-config-editor-firefox 2 - Enter a search term '''autoplay''' media.autoplay.default '''1''' this correspond to the situation Block Audio media.autoplay.default '''5''' this correspond to the situation Block Audio and Video media.autoplay.default '''0''' this correspond to the situation Allow Audio and Video About, media.autoplay.blocking_policy, you can test '''2''' Double-click on the preference '''media.autoplay.blocking_policy''' enter a new value '''2''' click the Save button to save the change