Bug in ruler scaling

I think I found a bug in the ruler/scaling.

When I'm using other than a 1:1 world scale (maybe even that but I'm assuming not or there would be more complaints)

Refresh stop working. Pages go blank, no change in magnification or switching tools or changing options does squat. Usually appears in the first 2 minutes of the app running.

Very annoying and the only answer has been to close the file and program and start again.

Anyway... always good for a poke, I've been trying everything. I know it is something here or there would be a mountain of reports.

It's the rulers! Turning the rulers off and on brings the display back to normal.

David Milisock's Blog can you check this bug hasn't been carried forward, please.