"file not found" error

BahamutZERO

For the past half hour or so I've been getting an error when loading pages here, or sometimes in the popup that mentions drafts being saved or errors about reactions not going through, which simply says "file not found" in plain text on a blank page (when it's a full page reload and not the popup). The error goes away in a few seconds and the page loads properly after reloading again, but reloading immediately does reproduce it for a bit when it first happens. Just before this started happening I saw a site undergoing maintenance page for a bit when I refreshed, something may have broken then.