Clone tool's target area has been replaced by 2 slanting pens

I've been accustomed in Photo-Paint 2018 (and earlier) to use the clone tool whereby the source is a circle/square with a plus and the target is a circle/square. Now, presumably because of a change I made inadvertently, the target is denoted as 2 slanting pens with tips slanting to the left, which seem to indicate the circle/square target area but don't actually show it. look (taken from Photo-Paint 2017). Unfortunately, I cannot show this in a screen shot, as the slanting pens aren't captured in the shot.

How do I get back to a target area denoted by circle/square?