I've noticed lately that depending on what zoom level I'm viewing my document in Adobe Acrobat, my table borders will disappear and come back.
For example, here is a table in my most recent homework seen at 125% zoom:

Here is the same document, now viewed at 150% zoom:

I write my documents in Overleaf, and it happens no matter which machine I'm on (school and home). I guess in the grand scheme of things it's no big deal, but it does bother me to think my documents may not be displaying as I want them to on the receiving if the person viewing it changes their zoom.
Any ideas?
\arrayrulewidth=1ptto circumvent this. – Arzigoglu Feb 23 '17 at 05:26