Latest hotfix or something must have fixed it, working now! Prior to that, tried many different browsers (Chrome, Chromium, Safari, Edge, Firefox), on many different machines (Android, ChromeOS, iPhone, Windows, Mac, Raspbian) with many forced refreshes, browser installs, et cetera (even reinstalled an OS in an unrelated project).
Edit: Thanks Rob, FlyTeach, and CharlieLuce for providing suggestions.