This happened to me the first time since HF20 went live.
After claiming some of the discounted accounts, I wanted to make an upvote on somebody's post. And was hit by a surprise

I never ever have seen this banner before. I said

"WHAT ?"

In no time I went to steemd.com to see what is going on.
And there it was - a NEGATIVE MANA

A complete paralysis. All zeros. No votes, no comments, no transfers nor power up was possible.
I have never ever heard this is even possible. It took me about one hour to get into positive figures again.

You never know when you will get to learn something new. :)

@onealfa