blocking error

[digitalis]

Hi Johannes,
Today I had a blocking error when I tried to create a new selection.
Jpeg of the screen included.
Regards.

[cajomi]

I also had this error. The problem is caused by a callback and appears seldom and randomly. I hope I get it solved for final release.

[Jules Verne]

I got it just the once so far, in my case it seemed to be from selecting/deleting isolines very quickly.