MediaWiki:Common.css currently doesn't support Collapsible tables, basic code can be seen at MediaWiki:Common.js on wikipedia.
While Collapsible tables are not overly common in wikias they offer an easy way to pretty up pages with walls of text or code/supplementary type data that some users are disinterested in seeing. Raulfin Talk 10:06, April 7, 2015 (UTC)
- I don't really mess with css, the admin that handled that stuff disappeared awhile ago.
◄► Tephra ◄► 17:37, April 7, 2015 (UTC)
Found some info in the community:Help:Wikitext_best_practices page. The wikia will recognize class's mw-collapsible and mw-collapsed but not collapsible and collapsed as the help page says, it may need to be verified and updated. Raulfin Talk 08:01, April 10, 2015 (UTC)