Hover Scrub doesn't output to Mercury Transmit

As per title: when hover scrubbing in icon view in 15.3.0b13 image not sent to monitor via Mercury Transmit, unlike in the release version 15.1

Also system info doesn't seem to get copied to clipboard.

Win 10x64,

NVidia GTX980 461.40

i75930K, 64GB RAM, etc etc.