blog_portal-downloadable-csv-2.liquid

[...]

    <div id="csv_data"></div>

    <script type="text/javascript">
        // '/odata-web-pages' is where I published the sample FetchXml-generated feed
        fetch("/odata-web-pages?website-id={{ request.params['website-id'] }}")
            .then(response => response.json())
            .then((data) => {
                const link = document.createElement("a");
                const linkText = "Download Csv file";

                let csvContent = "data:text/csv;charset=utf-8," + encodeURIComponent(data.map(e => e.join(",")).join("\n"))

                link.append(linkText);
                link.setAttribute("href", csvContent);
                link.setAttribute("download", "your_csv_data_file.csv");
                link.setAttribute("title", "WebPage CSV Download");
                
                $("#csv_data").append(link);
            })
            .catch((error) => {
                console.error('Do something with this error:', error);
            });
    </script>

[...]

Updated line 13 to encodeURIComponent CSV content. This handles special characters such as # which prevented full download