Heroku 通过cname设置HTTPS时出现问题

所以我在heroku上开发了我的RoR网站。我在heroku上使用了https，最近我为我的网站购买了一个域名。因此，我将www.mydomain.com设置为cname，将其设置为myapp.herokuapp.com

但问题是，当你浏览www.mydomain.com时，你会收到浏览器警告 说

我想知道如何在您浏览到时显示此错误来修复此错误

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感谢您的帮助

如果您想在自己的域上使用SSL，您需要为您的域购买SSL域，然后使用Heroku SSL端点插件（每月20美元）

You attempted to reach www.mydomain.com, but instead you actually reached a server identifying itself as *.herokuapp.com. 
This may be caused by a misconfiguration on the server or by something more serious. 
An attacker on your network could be trying to get you to visit a fake (and potentially harmful) version of www.mydomain.com.
You should not proceed, especially if you have never seen this warning before for this site.