It seems that the extension is hardcoded to show only the article title as bolded and the rest is plain text. However, I wish to have page previews similar to Wikipedia, where the bolded text is as shown in the article with contents in parenthesis is left out. Is there a means of getting this? Can this be done in MediaWiki:Common.css? If so, does anyone know a code?
Topic on Extension talk:Popups
As of now this is intentionally hard-coded in the Popups extension as well as in the TextExtracts API that serves the text snippets.