Can someone please take a screenshot of this "shading between posts" issue and annotate with arrows or something so I can see what you mean, as I really don't understand.
You're going to have to be a bit more specific.
At the very least are you using the light theme or the dark theme, and mobile or desktop?
(My eyes are shocking, frankly, and I do fine with the light layout as it is. However, if I'm having a "bad eyes day" I hit command+ on my Mac which ups the...