How to use:
{{#widget:Searchbar
|page=<name of the page you wish to consult, required if using WSSearch, default: 'Special:Search'>
|altsearch=<term/search, default: 'search'> <requires 'term' if using WSSearch>
|placeholder=<text you wish to show as placeholder, default: 'Search...'>
}}
Example output (WSSearch):
{{#widget:Searchbar|page=Search|altsearch=term|placeholder=This takes you to 'Search'.}}
Example output (Defaults):
{{#widget:Searchbar}}
Example output (Default but placeholder):
{{#widget:Searchbar|placeholder=Zoeken...}}