I updated some SSL certificates last week (which even required contortions such as moving to a new issuer since some legacy software requires old-style SHA-1 signed ones which our current one doesn't provide), and it didn't take more than one (long) day of work.
The original argument was that seeing error messages often will make users ignore them, but I don't think certificate errors should be very common now. Either way, I think we should be encouraging users to read error messages more carefully. Maybe the Yes/No buttons on the dialog should be put in a random order, and the question randomly flips between "Do you want to proceed?" and "Do you want to abort?"... adding a "learn more" option would be a good idea too.
And since the former is (sadly) pretty common, this only teaches people that these warnings are not that unusual, and can safely be overridden.
It would be much better to have one "the server admin forgot to renew his certificate" type of warning and another "a totalitarian regime is trying to spy on you" type of warning...
Enjoy the simplicity
If I understand right, getting a replacement cert doesn't result in a change of the private key anyways.
It's just magically, on the expiration date, your cert is somehow insecure and we must treat it as if YOU ARE IN DANGER!! - even though it's still better than then plain HTTP that everyone uses every single goddamned day. Hell, a self signed cert is better than plain HTTP, yet for some backwards-ass reason we treat it as worse, despite the fact it makes you immune from passive eavesdropping and any injection attacks, which the average person is a lot more likely to run into than a self-signed cert being used by an attacker to MITM you.
CA's are a scam and a racket. I can't wait for Mozilla's Let's Encrypt[1] to come along and put them all out of business, hopefully before the last decade or so of training users to ignore the wolf-crying cert warnings comes to fruition.
Yeah, this is irresponsible on Manjaro's part, they know the rules of the game, but the game is broken!
Being able to inject traffic is not "passive".
In Firefox, yes. But not in Chrome (in my experience).