chromium/content/test/data/android/webshare-csv.html

<!DOCTYPE html>
<html>
    <head>
        <title>Web Share</title>
        <script>
            function initiate_share() {
                if (navigator.share === undefined) {
                    window.document.title = 'Fail: navigator.share === undefined';
                    return;
                }

                // Test standard MIME type "text/csv",
                // and also "text/comma-separated-values".
                const first = new File(['1,2'],
                                       'first.csv',
                                       {type: 'text/csv'});
                const second = new File(['1,2,3\n4,5,6\n'],
                                        'second.csv',
                                        {type: 'text/comma-separated-values'});
                const data = {files: [first, second]};
                navigator.share(data).then(() => {
                    window.document.title = 'Success';
                }).catch(e => {
                    window.document.title = 'Fail: ' + e;
                });
            }

            window.addEventListener('load', () => {
                window.addEventListener('click', initiate_share);
            });
        </script>
    </head>
    <body>
        WebShare Test!
    </body>
</html>