Are we just one tweetstorm away from a crash?
As @martinsmith suggests it is related to the current POTUS using Twitter.
Tweetstorm was used by ZeroHedge in their December article about Trump's tirade on US companies moving manufacturing jobs out of the US.
It is interesting that Dubravko would bring up this possibility, as many market participants are very keenly aware the effect of Trump' tweets on price movements.
The link no longer works, and one might wonder if the host was asked to bring down the page.