I have the same issue on gallery. We have mixed horizontal and vertical photo.
We have issue on vertical photo. Also if i cut the thumbnails 500×333 and leave the photo for example 2000×3000 i see an error during the view …
Hi, i just checked your url and i see that you have cropped the thumbnail of your vertical images to square like aspect ratio, but the full photo is still vertical, so the thumb and the full photo doesn’t have the same aspect ratio, you should preserve aspect ratios when generating thumbs, you can do this by resizing thumbs by only height (400px should be fine), as you can see in our demo site, vertical and horizontal images play well together;