Created attachment 106169 [details]
Two documents wit links to each other that should open the other document in a new window.

Based on this question:

https://tex.stackexchange.com/questions/372181/how-to-add-a-link-that-opens-a-different-pdf-in-a-new-window

Using LaTeX I generated two files (in attachment) with links to each other that should open the target document in a new window. However, instead of doing this, the target document replaces the current open document.

I suspect this is a problem with okular, since Acrobat Reader 9.5.5 opens the document in a new instance as desired.