We should include the protocol in the ajax popup for shortened URLs and Special:UrlShortener.
Thanks for your interest! This is about the UrlShortener extension (see "Tags" on the right).
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Hello @Aklapper and @Legoktm , I tried to reproduce the setting and installed the UrlShortener extension via using the vagrant way, as explained on the extension page. However, I do not see any ajax popup during the shortening process. A clear explanation of how to encounter the issue would be helpful.