Make a link look right when it’s shared CARD
How a link looks when it is posted (the title, description and big image) comes from a few meta tags people usually guess at. This writes them right, checks them, and shows the card each platform will draw.
Your page
Tags and preview
How it works
The one that catches everyone
The image. og:image has to be an absolute https URL, because Slack, X and Facebook fetch your page from their own servers where a relative path means nothing, which is why a link previews fine to you and blank to everyone else. Make it 1200×630 and set the width and height. CARD flags a relative or missing image before it costs you a share.
Doing this often? OBSCURA Umbra edits the site's files where they are and previews the pages, with search and replace across the folder. On its own, US$4 a month; with everything else, US$9 a month or US$79 a year. 7 days free.