msgRef.current is null but got check undefined in the ContentEditable component causing app crashed

[necrosource-bot]

I am facing an error that it'll crash the app entirely. When I traced the error, it shows into this part:

if (typeof msgRef.current === "undefined") {
  return true;
}

Based on the error, I think the above line should be checking for null not undefined right. Someone please help, thanks a lot!!

Originally posted by @tunglamforwork in chatscope#173