Disable autoplay of videos - Source
in about:config you can set media.autoplay.default to 1 in order to block automatic playback on all pages or set it to 2 to decide on a per domain basis.
media.autoplay.default media.autoplay.allow-muted // Autoriser autoplay pour vidéos mutées, mettre false
Désactive openVR, empêche SteamVR de se lancer pour rien sur facebook ?
dom.vr.openvr.enabled
Désactive l’auto-remplissage relou quand on tape dans la barre de recherche - Doc
browser.urlbar.autoFill
Empêche backspace d'ouvrir la page précédente
browser.backspace_action // 0: Goes back in history | 1: Acts as Page Up | 2 (and above): Does nothing
WebRTC (needed for Discord in browser) Source
media.peerconnection.enabled // boolean
Disable the need to press enter after clicking on the search engine in the bar : Source
browser.urlbar.update2.oneOffsRefresh // false
Settings/Options > Advanced > General > Config Editor…
toolkit.legacyUserProfileCustomizations.stylesheets > true