Need JS to open link to another page in same PDF in new document window

I am on a Mac using an old version of Acrobat  - 9 Pro. I have created a multi-page PDF with internal links. For most of the internal links, i want them to jump within the same document window, so my Acrobat document preference is set accordingly. However, there are a handful of links that want to open in a new document window so that the user has both pages open at the same time for reference.

My original file is in InDesign. I see no way to add JS scripting to a button there. In the PDF, i can set the actions to link to a new page, but there's no where to specify "in a new window."

I'm hoping there is a javascript that i can apply to these few buttons that will accomplish this. Any help/advice is appreciated.

~bexterinni