I am testing a new feature in development for 1999.io.
When you add a margin image to a post, it's also used as the image in the metadata that's transmitted to Twitter and Facebook in the HTML <head> section. This is not optimal. Because the image used in the right margin is usually too low-resolution to work in the context that Twitter and Facebook use them.
So I added a new payload value, imageForMeta, which is the URL of an image that should be used in the metadata. If it isn't specified, we use the low rez image, if specified.
This post has a nice high rez image of Abraham Lincoln as the imageForMeta. Let's see if Facebook and Twitter pick it up.