@macky I’ve spent some time today with the white line issues and I’ve narrowed it down to a Chrome rendering issue. I don’t get it in Firefox or Safari, I’ve had issues with this type of thing with chrome in the past (outside of blocs created webpages also), it’s something todo with the images being really big and then being scaled down in the browser.
I’ll do a little more research and see if this is a know chrome rending issue or a fix that can be applied.