Og:description meta tag for slack app link unfurling

Question

Is og:description or twitter:description tag necessary for slack to unfurl html page's link contents ?

I have a link with og:title , type , url , image and description tags . Slack app unfurls the link fine . But when I remove the description tag or if set the content of description tag null , then nothing is unfurled .

Ideally besides description other things should have been previewed in slack . How is title and image and other things dependent on description tag ?

Answer 1

Slack displays og:description tag, not twitter:description. Title and image don't anymore depend on description tag. Even when og:description is null, removed or spacefilled Slack generates social snippet.

In case description is not provided Slack is able to display a title up to 2000 symbols.

Slack uses a combination of Open Graph and Twitter tags to unfurl links as shown in Slack API Documentation

For generating purposes Website Open Graph Generator is useful. For validating FB Sharing debugging is handy.