PDF Viewer Grayed/Greyed Out

How I can use the grayed out buttons in the pane viewer for PDFs. I have the Microsoft Suite, Adobe, and Foxit. If I go into the slideshow, that seems to provide the functionality, but not in the preview pane. At one point, this worked, but no longer does.

The problem is discussed here, but the Opus 13 version doesn’t seem to match any suggested fixes.

There’s talk about the shell settings possibly, but I cannot figure that out either.

Any help that someone could provide would be greatly appreciated.

This issue has been raised before, but I am working in Opus 13 and the interface seems materially different.

Nothing about how PDF viewers work in Opus has changed as far as I can think?

PDF viewers work using an API that doesn't normally expose zoom in/out methods that the host program can call, so Opus's own zoom buttons won't work with most PDF viewers. But most PDF viewers have their own zoom controls within the viewer itself.

Exactly how they work or where they appear depends on the PDF viewer (Adobe, FoxIt, etc.).