A user hexworks reports that after upgrading their Discourse forum from 2.6.0.beta4 to 2.9.0.beta4, link embed previews (oneboxes) no longer generate for certain URLs — though they worked previously. Screenshots show the difference: the older version displayed a preview, while the newer one does not. JammyDodger notes that even the older version didn’t generate a true onebox and suggests the issue lies with the target site’s lack of oEmbed or OpenGraph metadata. itsbhanusharma confirms this is not a Discourse bug, explaining that previews can only be generated if the linked site provides the required oEmbed tags — and provides a test link via iframely.com to verify this. The topic has been moved to Product Support for further assistance.
I’m updating my Discourse forum from 2.6.0.beta4 to 2.9.0.beta4 and I’ve noticed that when I’m trying to create a topic it doesn’t generate embeds for specific links in the new version (works in the old version) 
2.6.0.beta4:
2.9.0.beta4:
I’m pasting the same link in both versions 
How can I fix this? I did a clean install and I’m testing the new version. Neither installation has plugins, so it is not the case of a missing plugin.
The first one doesn’t seem to have created a onebox either? It should look a little like this:
I think you would need the site you’re linking to include the relevant oEmbed/OpenGraph tags for it to function properly.
This isn’t a discourse bug.
The site you’ve mentioned does not have the relevant oEmbed Tags so a preview can not be generated unless the said website actually starts supplying the necessary links.
in the meantime, I’ve moved this topic to Support
