http.response.content_type.media_type
http.response.content_type.media_type String  The lowercased content type (including subtype and suffix) without any extra parameters, based on the response's Content-Type header.
The field value will not include parameters such as charset.
Example values:
| Content-Type header | Field value | 
|---|---|
text/html | 
"text/html" | 
text/html; charset=utf-8 | 
"text/html" | 
text/html+extra | 
"text/html+extra" | 
text/html+extra; charset=utf-8 | 
"text/html+extra" | 
text/HTML | 
"text/html" | 
text/html; charset=utf-8; other=value | 
"text/html" | 
 Categories: 
    - Response
 - Headers