Currently running Firefox 64.0 Quantum on Ubuntu 18.04 -- fresh install on a new computer. My settings save, but Firefox just ignores them. I tell it to open all links in a new tab, and it consistently opens them in the same window. I tell it to open all new windows and tabs with the home screen, and every single time it wastes my time by loading the last session before it does what I need at the moment. I'd switched to Opera years ago on other computers because Firefox had gotten too clunky but had hoped to come back to it with this new laptop. But that's not happening if it can't even follow basic instructions.