I wanted to update this thread as in further testing, I've noticed that the odd shadows are not relegated only to corners. I created a video to demonstrate how objects positioned in close proximity to a wall also have shadows behaving strangely.
I took a look at one of my older builds while testing another issue and noticed the strangeness, especially with the Boom Cube object that I used in it:
This effect of an almost transparent edging or shadow on the object definitely didn't exist when I originally created and published the build.
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