Resource interpreted as Image but transferred with MIME type text/html

Chrome Developer Tools Console 显示：

Resource interpreted as Image but transferred with MIME type text/html: "http://img.webscan.360.cn/status/pai/hash/51c10833cd63ae1306cfc20c81f96298"

按字面理解，意思是请求的资源是图像，但传输的内容MIME类型是text/html。

网页源代码为：

<img border="0" src="http://img.webscan.360.cn/status/pai/hash/51c10833cd63ae1306cfc20c81f96298"/>

此图像没有后缀名。

Network 中点击此图像文件名，Headers 工具显示：

Remote Address:220.181.158.213:80
Request URL:http://img.webscan.360.cn/status/pai/hash/51c10833cd63ae1306cfc20c81f96298
Request Method:GET
Status Code:200 OK
Request Headersview source
Accept:image/webp,*/*;q=0.8
Accept-Encoding:gzip,deflate,sdch
Accept-Language:zh-CN,zh;q=0.8
Connection:keep-alive
Cookie:__huid=
Host:img.webscan.360.cn
Referer:http://www.360.cn/
User-Agent:Mozilla/5.0 (Windows NT 5.1) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/35.0.1916.114 Safari/537.36
Response Headersview source
Connection:close
Content-Encoding:gzip
Content-Type:text/html
Date:Wed, 21 Oct 2015 12:21:16 GMT
Server:360Server
Transfer-Encoding:chunked

可以看出，请求的是image/webp，返回的是Content-Type:text/html

网页能正常显示图片

Resource interpreted as Image but transferred with MIME type text/html

此消息仅为提示，正常时可不予理会。