Yep the Bob's Logistics Belt Reskin helps a lot, but I still can't unsee the seams.

look closer and you'll see that the yellow belts are also affected by this (png format is realy a pain when you want to capture small details) it's quite subtle only single digit pixel wide, and if you don't believe me just load the save. If you don't have any seams on the yellow belts it just means...

So the bug about the seam between belts in mapmode ( https://forums.factorio.com/viewtopic.php?f=48&t=84602 ) I have it in normal view and it seems to affect any belts, it's just that the basic belt (bob's mod) being grey is showing it more. on the yellow belt it shows more on its shadow. On my ...

So when I zoom at the max and then dezoom 4 steps a line appear on some basic transport belts (bob's mod). Seems to only affect upward belts.
Don't know if it's only the modded belts or all of them. "Literally unplayable".

Seablock.zip is the savefile.