Stacked layers in timeline not showing

I am fairly new to Resolve, coming from Premiere for reference.

I have a 1080x1350 comp, 4:5 aspect ratio (vertical orientation) and I am going to display a clip in the middle with a couple stills on top and bottom to frame it. This is going to be used for an instagram post.

The issue I am facing is that when I layer the images...with the featured (middle) clip on track three, when the clip is centered in the composition the layers underneath do not show. I only see black where another image should be showing. As if there is no alpha. As soon as I move the featured clips position (even by one pixel) the images underneath appear. The issue is that I want the featured clip exactly in the middle of the composition. Am I missing something? Is this an error?

In premiere it automatically shows whatever is underneath the top track. Regardless of the position of the top clip. in theory you could layer 20 clips and they'd all show given that the positions were correct.

Here is another explanation if it's helpful

Track 3 - Featured clip (16:9 video)
Track 2 - image to fill top of frame (black space above the featured clip)
Track 1 - image to fill bottom of frame (black space below the featured clip)


Tracks 2 and 1 ONLY SHOW if I move the position of the clip in track 3..

Can you try to crop a pixel on the image and see if trigger it?

This behaviour has been discussed before in multiple posts. I am not sure when BMD is going to fix it.

https://forum.blackmagicdesign.com/viewtopic.php?f=32&t=99466

You can "fix" this issue by cropping the clips by a tiny a value, even less than 1. It seems that if they all occupy the allotted space, it won't work.

I find that changing Opacity of the top clip to 99.99% also works to restore the missing alpha.