Did it not get better with FF 70 for you? They switched the rendering to use a better API on MacOS: https://mozillagfx.wordpress.com/2019/10/22/dramatically-red

Did it not get better with FF 70 for you? They switched the rendering to use a better API on 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...