From 2017-07-20 meeting with @dr0ptp4kt @Fjalapeno and @ggellerman
Existing user documentation in the sense probably meant here is at https://www.mediawiki.org/wiki/Help:TemplateStyles
See also https://www.mediawiki.org/wiki/Extension:TemplateStyles.
Thanks @Anomie !
There is an example here.
Do you want more examples, or can this task be closed?
Yeah, I'd like to add a few more examples (not so much as documentation but as a showcase of what kind of use cases are enabled by TemplateStyles).
@ggellerman, @Tgr: please review https://www.mediawiki.org/w/index.php?diff=2625942 and close this task if what I've done is good enough.
The page looks like it contains decent enough examples, so this can be considered resolved. More examples can be added at a later date if it is considered to be useful or needed.
Thanks, @Nirmos !