Mute new tabs by default in Firefox
Is it possible to tell Firefox to open new tabs with muted sound by default?
You can use the Mute Tab add-on:
About this Add-on
Current tab context menu items:
- Mute/Unmute All Tabs
Current add-on settings:
- Auto-mute new tabs
- Mute Tab while holding a certain key
Source Mute Tab
New tabs are typically given focus immediately when they are created, so this won't help in that case. Only new tabs opened in the background would be muted this way by default until you make one of them active.
Firefox 55.0.2 (64-bit) in Ubuntu 16.04:
about:config [I accept the risk!]
Search: media.block-autoplay-until-in-foreground [Double click the search result line to toggle the value between false and true.]
Reference: https://www.ghacks.net/2016/11/14/firefox-51-blocks-automatic-audio-playback-in-non-active-tabs/