Upgrading to v2.8.3

Hello, I would like to upgrade Cockpit to version 2.8.3, the latest published version. When I download cockpit-core.zip, unzip, upload to XAMPP, run /install, and navigate home, I get the following page. I have not modified the folder in any way. What could be the reason I am getting this?

Installing works on server fine. I will work on this on the production server. The problem is my local install. I am using a fresh install of XAMPP on Windows 11 with Apache installed with GD enabled, the rest are set to defaults. I unzipped to the htdocs folder and started the local PHP server, but after /install, I just get the 404 page.