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/* This script adds a link saying "Sticky headers" under "Tools".
   The link reloads the current page with this gadget:

   Make headers of tables display as long as the table is in view, i.e. "sticky"
   (requires Chrome v91+, Firefox v59+, or Safari)

   It displays incorrectly or poorly on some tables.
   The gadget itself can be enabled permanently on the "Gadgets" tab at Special:Preferences.
   This script should not be used if the gadget is enabled.
   To remove the sticky headers again, navigate away in the browser,
   e.g. with a back button or "Article" tab.

   To use the script, add the following line to Special:MyPage/common.js:
 
importScript('User:PrimeHunter/Sticky_headers.js'); // Linkback: [[User:PrimeHunter/Sticky headers.js]]

*/

$.when( mw.loader.using( ['mediawiki.util'] ), $.ready ).done( function() {
  mw.util.addPortletLink(
    'p-tb',
    location.href.replace( location.hash, '' ) + ( location.search ? '&' : '?' ) +
    'withJS=MediaWiki:Gadget-StickyTableHeaders.js&withCSS=MediaWiki:Gadget-StickyTableHeaders.css',
    'Sticky headers',
    'pt-stickyheaders',
    'Reload page with sticky table headers',
    null,
    '#t-recentchangeslinked'
  );
});