Specifically it made #285 `fix.pasteOpts` hard to test because this code sets a timeout to clear the (initially empty anyway) textarea when the math field is created, and the test case would, synchronously after creating the math field, paste in some text, so `saneKeyboardEvents.util.js` would set a timeout to check the textarea for pasted text, but by then the unnecessary timeout from this blur would have cleared the textarea.