By default, an internal link to a pop-up file viewer would cause the site to scroll over to where the PDF or image is at. Clicking out of the pop-up dialog box will keep the site in the same location as the linked PDF or image, and not back to where the internal link is at.
This behavior may cause confusion or experience difficulty for the site viewers while navigating within the site.
As of writing, the system cannot automatically scroll back to the internal link after the pop-up file viewer is closed, but this article covers a possible alternative that might work for your design.
To prevent the site from scrolling over to a linked pop-up file viewer
1. Create a new grid section.
2. On the left editing panel, under Visibility, tick Hide section.
3. In the hidden grid section, add the file to be linked to. This might be a duplicate if the file needs to be exposed or visible somewhere else on the site.
4. Create the internal link for this file, enabling the pop-up viewer.