If it’s on a “well-known” domain — eg, facebook.com — it’ll send you to the share page there. It checks to see if it can figure out if the site is on a known platform (currently Mastodon, Known, hosted WordPress, micro.blog, and a few others). If so — hooray! — it knows the share URL, and off you go. It looks for a header tag on the page. The href attribute should be set to the share URL for the site, with template variables
{text}and (optionally){url}present where the share text and URL should go. (If{url}is not present, the URL to share will be appended at the end of the text.) If it’s there — yay! — we forward there, replacing{text}and{url}as appropriate.
I’ve been looking for ways to improve sharing to the open web and this tool looks neat. Wish the source code was available though!
