I've tried on both a 24" widescreen (16/9) monitor as well as a 56" widescreen monitor.Curious to know what you're viewing them on which is showing you them horizontally...what I've viewed them on, more than one computer with large widescreen displays, they have all been stacked vertically. So, I'm not disputing your statement but rather just asking for my own information.
When viewed in Chrome, yes the pictures do display vertically, but I don't use Chrome all the time. My normal browser of choice is IE 11...
...and it will only display pictures properly when there's a carriage return added.