}
        // Block URLs that look like protocol:// (unknown protocols)
        if (/^[a-z][a-z0-9+.-]*:/i.test(trimmedUrl)) {
            return '#';
        }
        // Allow other relative URLs (may contain colons in path/query)
        return url;
    }

    /**
     * Get file type icon based on URL or mimetype
     */
    function getFileTypeIcon(url, mimetype) {
        if (mimetype) {