This template is used in system messages, and onapproximately 353,000 pages, or roughly 1% of all pages. Changes to it can cause immediate changes to the Wikipedia user interface. To avoid major disruption and server load, any changes should be tested in the template's/sandbox or/testcases subpages, or in your ownuser subpage. The tested changes can be added to this page in a single edit. Please discuss changes on thetalk page before implementing them.
Note: This template does not hide anything for mobile users (phab:T111565).
Syntax
{{Hidden begin| showhide=<!--"left", otherwise omit-->| expanded=<!--"true", "on", yes", etc, otherwise omit-->| class=| width=| border=| bgcolor=<!--background color for both the title and content-->| style=| ta1=| titlebgcolor=<!--background color for the title-->| titlestyle=| title=| ta2=| contentbgcolor=<!--background color for the content-->| contentstyle=}}<!----[content to be hidden placed here]---->{{Hidden end}}
