GNURadio fails to generate flow graph

Was away from GNURadio for about a month and when I came back, none of my flow graphs built at all.

Using Ubuntu 18.04 dual booted from Windows 10 with GNURadio 3.9

Attached image is the error it’s throwing

Image in replies is the flow graph I’m trying to work with (although neither new nor old flow graphs generate now)

image

Thoughts?