The root cert for www.schrauger.com is StartCom Certificate Authority. Isn't it their (StartCom's) responsibility to make sure the owner of Certification Authority of WoSign (the next cert in the chain) is acting in accord with some terms and conditions? Secondly, should the browser vendors remove StartCom CA as a trusted root? Do they not do that because all the StsrtSSL sites would break? Fine with me, personally.
[Edited to clarify who "their" meant]