In Swedish Wikipedia css code from TemplateStyles are shown in article extracts in search results in some searches:
For example first item "Alec John Such" in this search shows:
"nested-talk{border:1px solid#c0c090;background-color:#f8eaba;width:100%;margin:2px 4px}Alec John Such, född 14 november 1956 i Yonkers i New York, är en amerikansk musiker"
and third item "John Entwistle" shows:
".mw-parser-output .infobox.geography .maptable th{border:0;padding:0}John Alec Entwistle, född 9 oktober 1944 i Chiswick i västra London, död 27 juni"
Those articles contains templates that get their css from TemplateStyles tags.