Mouse hovering over slide panel AND what's beneath

[Jeffrey Bloch]

In the attached video, you'll see a portal at the back, then 2 independent slide panels. As I hover over one, the portal in the back is not effected. As I hover over the slide panel to the right, you'll see the portal rows reach to the mouse hover. Any thoughts why this happens over one slide panel but not the other? The panel in question contains a rectangle at full opacity.

 

FM 19

 

Thanks!