There have been no changes to the website in several months, so nothing should have changed. It is most probably a corrupted cache in your web browser OR a browser instance that is on the verge of crashing (which can be addressed by either full and proper reboot, not sleep or hibernation, or fully logging out of your OS session, as in logout of your regular OS user session/desktop, then log back on) which will forcibly close any browser instances that have gotten hung up in the background and can corrupt the shared memory with the active browser window.