Fixes #18444. Inside of UrlPreviewer, we need to combine two dicts (one from oEmbed, and one from OpenGraph metadata in the HTML) and in Mastodon's case they were very different. Single Page Applications (SPAs) seem to sometimes provide better information in the OpenGraph tags than the oEmbed stubs, because the oEmbed stubs are filled in with JavaScript that Synapse does not execute. This change improves previews on Mastodon and YouTube (for the same reason). Tested to not regress previews of Twitter or GitHub.
104 B
104 B