I have a problem that I didn't anticipated that could be a problem.
I have a simple flow that makes a print-screen on a web page, and after that the picture is printed on default printer.
The problem is that the printing goes awry and is printed on the previously manually selected printer.
How can I print a picture on a printer that I have selected as default (from flow)
The final goal of my flow is to print that pictures alternatively on two printers. But for that i must surpass that surprising issue.

The "Set default printer" is working , I see in "Device and printers" how default printer is modified. The problem is that it doesn't change in printing app interface.