Do you know, that… ?

Most people working with sheet metal know about the technological requirements in the corners. This is a separate topic. I will mention, it's about an operation Corner undercut, which can be made on an unfolded or bent model.

However, today they will present another option, which is responsible for a delicate indentation in the corner visible only on the unfolding.

That such an indentation would be visible, you must uncheck Corner finish w Corner options. All visible options are available by right-clicking on Flat-Pattern.

ticking Corner finish you will get solution as below.