I'm sorry, I really wouldn't know what's happening there. On my Linux, Chromium works the best, Firefox can pass, Opera is a bit slower, and Epiphany (is that the name?) chokes a fair bit.
On i3, Windows things seem fine - I tried Edge, Chrome, and Firefox.
On Mac, I somehow managed to get it working based on Lambda Test web interface feedback, but I wouldn't know the real use performance.