Rotate Region causing crash

[tkbd]

I compared about behavior other rotation commands in the magnet mode.
(I use the no modified region_rotate plugin file in v2.1.5.)
Rotate Normal and Regon behaver there is a similar part.

For example Even when these two commands in magnet mode,not instructed for 2ndary selection for magnet boundary set.
Is it a specification or a bug?

And I found another interesting message in other rotation command.

Make a cube,and all faces select ,and inset x2

Then did Face mode:Rotate > Free (with Magnet mode (use click + Alt key ))

Message dialog: Magnet Rotate on multiple face regions reguires an explicit rotate origin.

This message may indicate a special condition in the magnet mode.
I wish it will be a hint to the solution of the problem.

Cheers.