Or just disable mp4, webm, flash altogether in about:config. I typically view media in specially sanctioned browsers, just for viewing rich media. E.G Chrome o

Or just disable mp4, webm, flash altogether in about:config. I typically view media in specially sanctioned browsers, just for viewing rich media. E.G Chrome on windows 10 hooked up to a 4K Acer monitor via HDMI You can harden FF also and remove a few other annoyances like the default PDF reader, etc: https://github.com/pyllyukko/user.js/ https://github.com/pyllyukko/user.js/