I confirm that sometimes it happens to me with the latest beta 5.1.6.200. Also once the error occurs, maxthon becomes very unstable, to the point of crash Well, it gave me the same error in the stable version   ( screenshot more below ) I have deactivated the options (in case I had something to see) Use DirectWrite (Relaunch Maxthon for this change to take effect.) Use hardware boost mode (Restart the browser for this change to take effect.) But, the result is the same