Build a link card for a URL, asking fetchPreview for its metadata. Without a fetcher, or when it fails or finds nothing. The card falls back to the hostname as its title. Resolves null when the URL is not an http(s) link.
fetchPreview
Optional
Build a link card for a URL, asking
fetchPreviewfor its metadata. Without a fetcher, or when it fails or finds nothing. The card falls back to the hostname as its title. Resolves null when the URL is not an http(s) link.