Opening SCORM within the course - URL in new window

Hi everyone! I encountered a bit of a challenge, maybe you were there before and would be able to help. A simplified summary below.

I'm working on a course (A) that demands a button1, which takes you to another course (B). After visiting B, you should be able to close it and see A again (both of them are 'display in a new browser window'. I added the 'open URL' trigger to the button1, added the specific address and chose the 'display in new window' option.

When I click button1 and go from A to B, it kind of opens in a new window, but it's the same new window that A is already open in. So when I close B, I cannot see A. I have to go back to the course page and open A again. Do I have to tell you it's not an option? :)

Could you please advise me on what I am doing wrong here? :) (I've found 2 or 3 discussions on in, but none of them was resolved.)

Best! Emilia