Regarding the energy use, give 71 a try. It includes compositor enhancements (actually included in the last release) that should significantly reduce energy use

Regarding the energy use, give 71 a try. It includes compositor enhancements (actually included in the last release) that should significantly reduce energy use on modern macOS: https://mozillagfx.wordpress.com/2019/10/22/dramatically-reduced-power-usage-in-firefox-70-on-macos-with-core-animation/ https://mozillagfx.wordpress.com/2019/10/22/dramatically-red...