Firefox certificate warning page is skipped without me pressing anything
 

Out of the blue and while trying to visit a blog at .wordpress.com, firefox shows a certificate warning instead. Before I get a chance to click anything (such as Advanced to see what seems to be going on), the page disappears and the wordpress blog is shown. How can this be? Blog is frequently visited by myself without anything like this having been seen before.

I regularly visit a few blogs at Wordpress.com and have not encountered this behavior either. It could have just been a temporary glitch. I visited the site of a major newspaper in a western U. S. city the other day and, whenever I clicked on a headline, I got a 502. The problem cleared up in ten or fifteen minutes.

What was the website and the Firefox version? That information could help.