I thought (from posts from MNers, not from actual info from MNHQ) that it was mainly a Safari problem., basically, MN has not worked on Safari for at least 3 days. As you report problems with Firefox, it looks as if it's all Apple portable devices (iPhones and iPads) that are afflicted.
Yes, adblockers help enormously. I was resisting getting one (because I thought it was fair enough that M. Got revenue that way) but after 3 days if unusabilit, I followed the wisdom of others and installed Adblock Plus.