MediaWiki:Common.js

mw.loader.using('mediawiki.util', function () {
  $(function(){
    // Get the list of categories assigned to this page
    var cats = mw.config.get('wgCategories') || [];
    // Specify the category you want to target
    var targetCat = 'InternationalizationForms';

    // Only proceed if the page is in that category
    if ( cats.indexOf(targetCat) !== -1 ) {
      // Create and style the button-like link
      $('<a>')
        .text('📄 Export this page to PDF')
        .attr('href','#')
        .css({
          display:'inline-block',
          padding:'0.5em 1em',
          background:'#007bff',
          color:'#fff',
          'border-radius':'4px',
          margin:'0.5em',
          'text-decoration':'none'
        })
        .click(function(e){
          e.preventDefault();
          window.print();
        })
        // Insert it above the content area
        .prependTo('#content');
    }
  });
});