I gave up on Firefox and went back to Blink (via Qutebrowser) in part because of Mozilla's countless recent breakages, regressions, and inexplicable decisions,

I gave up on Firefox and went back to Blink (via Qutebrowser) in part because of Mozilla's countless recent breakages, regressions, and inexplicable decisions, but in other part because of exactly this problem. So many sites just break in mysterious ways on Firefox, and the reason why is inevitably some exception raised 50 frames down the stack in an obfuscated bundle of $FRAMEWORK_DU_JOUR goop I can't even begin to debug.