MediaWiki:Common.js

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mw.loader.using( 'mediawiki.util', function () {
    const g = mw.config.get( 'wgUserGroups' );
    if ( !g.includes('editor') && !g.includes('approver') && !g.includes('sysop') ) {
        mw.util.addCSS(
            '#ca-edit, #ca-edit-source, #ca-ve-edit { display:none !important; }'
        );
    }
});