Weinre: Refused to get unsafe header "Content-Length"

Weire 2.0.0-pre-I0Z7U9OV from https://www.npmjs.com/package/weinre. 

CORS/Ajax issue, server needs to add the header: Access-Control-Expose-Headers, see https://developer.mozilla.org/en-US/docs/Web/HTTP/CORS#Access-Control-Expose-Headers