I tested modifying
plupload.html5.js to:
triggerDialog:(j.ua.gecko&&h.FormData||j.ua.webkit || j.ua.windows)
from:
triggerDialog:(j.ua.gecko&&h.FormData||j.ua.webkit)
Fixed the issues with IE10. Hopefully IE 10 gets updated so this isn’t required in the future.
IE8 & 9 work with Silverlight or Flash.