"Is it really that much time/cost/effort to test one more browser?" As someone who has over the years all in all spend months of work on catering to FF, I say

"Is it really that much time/cost/effort to test one more browser?" As someone who has over the years all in all spend months of work on catering to FF, I say yes. It is not the testing. But the fixing of bugs that costs time. Time most buisnesses apparently rather invest elsewhere.