since now HTTPS pages are mainstream, we are surely to address HTTP as insecure with some visual indicators.

Chrome is going to do this

Since 61 is already released, I think 62 should be the goal so it wouldn't be too far from Chrome. Perhaps use the "Not Secure" text on 63, too? Firefox can't wait too long after Chrome, otherwise it is going to be the "browser where pages are safe".

Chrome has this in its 68 already. I wonder when this can happen for Firefox. If Firefox falls too far, it just becomes much less competitive

I would like to see this in Firefox, too, but I doubt this statement is true. Firefox won't become "muss less competitive" because it doesn't mark HTTP pages as insecure. By the way: I already see users complain about this feature in Chrome. I still think it's the right thing to do but I don't see any relation between this feature and competitiveness, that doesn't make much sense.