Error when copying a portion of a rule

When I try to copy and paste a small while expression from one section of a rule to another section inside the same rule I get the following:

The logs only show this:

and when I try to re-enter the rule I just get the first image. Also when I check for broken rules it tells me there are none:

I did not use the back button (just hit the done button). I'm going to rebuild the rule however I'd like to know why this occurred.

EDIT: I'm on the latest available release (

This is a known bug, with a fix coming in the next release.