The Allow Title-Only Onebox plugin, created by dsims, enables oneboxes for links without description or image metadata. pmusaraj suggested adopting this behavior in core, which martin agreed with and created a PR to add this feature. The plugin’s life was short-lived, as the core update made it redundant. dsims jokingly referred to it as the “World’s fastest deprecated plugin”. The community, including pmusaraj and lindsey, appreciated the quick resolution and adoption of the feature in core.
If a linked webpage is missing description or image metadata, Discourse will normally leave it as a URL and not onebox it. This plugin changes that behavior to allow for title-only oneboxes.
The description requirement was actually removed at one point (way back when it was a standalone gem) but then it was reverted a few months later, so I assume there was some reasoning not to do it.
I have only seen a handful of URLs in the wild that match this scenario, so I imagine there are some edge cases where it doesn’t look right.