This HTML page requires JavaScript to be enabled to render, as it is a self-extracting gwtar HTML file.
A gwtar is a portable self-contained standalone HTML file which is designed to nevertheless support efficient lazy loading of all assets such as large media files; it is a polyfill HTML header followed by a tarball of the original HTML and then all assets. (For a detailed description of the format, see Gwern.net.)
You are seeing this message, instead of the page you should be seeing, because gwtar files cannot be opened locally (due to web browser security restrictions).
To open this page on your computer, use the following shell command:
perl -ne'print $_ if $x; $x=1 if /<!-- GWTAR END/' < foo.gwtar.html | tar --extract
Then open the file foo.html in any web browser.
You are seeing this message, instead of the page you should be seeing, because the web server is incorrectly configured or does not support gwtar files. Please contact the server administrator for help with this problem.