I do feel that there’s a difference in kind between: “a website was built with Chrome in mind, and has problems rendering in Firefox”, and “a website was built specifically to degrade in Firefox”.

If no engineering time was spent on Firefox, and it’s broken in Firefox, that’s a Firefox problem.

If active engineering time was spent on _deliberately breaking_ Firefox, then yes, I don’t think that’s a Firefox problem. I think it’s a website problem at that point.