MacOS Sierra - why applications began to completely close when you click on the cross?

Question

macOS

Good evening! Recently, in MacOS Sierra, when you click on the "red X", applications began to close completely, although before that they were simply minimized. At the same time, there is a dot in the dock near the application, as before, which symbolizes that it is running. But the application is completely closed. Tried rebooting, didn't help. Already used to minimizing applications, and I would like everything to be the same.
UPD. I noticed that if you press command + tab, then there is an application there. But when you switch to it, its workspace is not displayed, but only its menu is displayed in the top panel.

Answer 1

the form is not the whole application. the form was closed - the application remained. That's why it hangs in running. I recommend to study makos, it is interesting))