For the love of God, why has Mozilla not suspended Comodo yet? Too big to fail, my ass -- give a few months of warning before the notBefore cutoff date, and everyone will have plenty of time to switch over to a competent CA.
Comodo has had many serious security problems, including issuing fraudulent SSL certificates and releasing browser extensions that break security. Details: https://news.ycombinator.com/item?id=11962371