SEO issue with Facebook/Twitter

So SEO was discussed in issue #101 for the Google crawler, but this is concerned with the Facebook and Twitter crawlers. They both do not interpret JavaScript, which makes it impossible to dynamically set open graph tags for different pages. The link [here](https://developers.facebook.com/tools/debug/sharing/?q=https%3A%2F%2Frsb.kriasoft.com%2F) shows what the demo RSB site looks like with the Facebook crawler.

Since Firebase currently [lacks support for prerendering](https://github.com/firebase/firebase-tools/issues/33) content, the pages need to be statically compiled. This means the initial HTML is downloaded and then React rebuilds the DOM for page transitions.

Without precompiling the HTML, every link to my site on Facebook uses the same image instead of ones customized for the content.

Start by reviewing issue #101 and the linked Firebase prerendering discussion, then inspect the demo site's initial HTML and how React handles page transitions. The work is done when Facebook and Twitter can read page-specific open graph tags from statically compiled HTML rather than receiving the same image for every link.

Written by the indexing model from the issue text.