This extends the SEO options added in 1.6.0 (https://yellowgrass.org/issue/conf.researchr.org/896):

Add option to set up the og:image meta property used by Facebook and other social media when sharing a link.
Also, add the og:title and og:description meta elements to each page next to the meta description and title elements.

Submitted by Elmer van Chastelet on 11 February 2019 at 15:20