Try pasting these this link on try.discourse.org:
The link’s title is Timecop1983 - Let's Talk (feat. Josh Dally) _ Remaster but the generated title in Discourse will be Timecop1983 - Let:
「いいね！」 9
It looks like the issue is at youtube_onebox.rb#45
The single-quote (') in the title isn’t html-escaped so it closes the attribute value early, which gets sanitized away
Edit: submitted a pull request
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Merged, thank you for your contribution 
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