function geofotoshow_shortcode($a) {
    $a = shortcode_atts([
        'show' => 'slideshow',
        'id' => '',
        'preview' => 'true',
        'lang' => '',
        'zoom' => ''
    ], $a, 'geofotoshow');

    $show = $a['show'];

    if ($show === 'both') {
        ob_start();
        include GFS_PLUGIN_DIR . 'includes/render-both.php';
        return ob_get_clean();
    } elseif ($show === 'slideshow') {
        ob_start();
        include GFS_PLUGIN_DIR . 'includes/render-slideshow.php';
        return ob_get_clean();
    } elseif ($show === 'map') {
        ob_start();
        include GFS_PLUGIN_DIR . 'includes/render-map.php';
        return ob_get_clean();
    }

    return '<p>⚠️ Unbekannte Ansicht: ' . esc_html($show) . '</p>';
}
add_shortcode('geofotoshow', 'geofotoshow_shortcode');

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<?xml version="1.0" encoding="UTF-8"?><rss version="2.0"
	xmlns:content="http://purl.org/rss/1.0/modules/content/"
	xmlns:dc="http://purl.org/dc/elements/1.1/"
	xmlns:atom="http://www.w3.org/2005/Atom"
	xmlns:sy="http://purl.org/rss/1.0/modules/syndication/"
	
	>
<channel>
	<title>
	Kommentare zu: d09621a5-ff63-4705-a90e-889bed7cf06a	</title>
	<atom:link href="https://dynamicspace.bike/feed/?attachment_id=5563" rel="self" type="application/rss+xml" />
	<link>https://dynamicspace.bike/d09621a5-ff63-4705-a90e-889bed7cf06a/</link>
	<description>...bin mal auf Reisen</description>
	<lastBuildDate>Sat, 01 Jul 2023 16:13:02 +0000</lastBuildDate>
	<sy:updatePeriod>
	hourly	</sy:updatePeriod>
	<sy:updateFrequency>
	1	</sy:updateFrequency>
	<generator>https://wordpress.org/?v=6.8.1</generator>
</channel>
</rss>