diff --git a/qutebrowser/test/utils/http/test_http.py b/qutebrowser/test/utils/http/test_http.py
index 7ee660905..7eb857b99 100644
--- a/qutebrowser/test/utils/http/test_http.py
+++ b/qutebrowser/test/utils/http/test_http.py
@@ -63,47 +63,5 @@ class ParseContentTypeTests(unittest.TestCase):
         self.assertEqual(rest, ' encoding=UTF-8')
 
 
-class ChangeContentTypeTests(unittest.TestCase):
-
-    """Test for change_content_type."""
-
-    def test_not_existing(self):
-        """Test without any Content-Type header."""
-        reply = FakeNetworkReply()
-        httputils.change_content_type(reply, {'image/example': 'image/jpeg'})
-
-    def test_mimetype(self):
-        """Test with simple Content-Type header."""
-        reply = FakeNetworkReply(headers={'Content-Type': 'image/example'})
-        httputils.change_content_type(reply, {'image/example': 'image/jpeg'})
-        self.assertEqual(reply.headers['Content-Type'], 'image/jpeg')
-
-    def test_empty(self):
-        """Test with empty Content-Type header."""
-        reply = FakeNetworkReply(headers={'Content-Type': ''})
-        httputils.change_content_type(reply, {'image/example': 'image/jpeg'})
-        self.assertEqual(reply.headers['Content-Type'], '')
-
-    def test_additional(self):
-        """Test with Content-Type header with additional informations."""
-        reply = FakeNetworkReply(
-            headers={'Content-Type': 'image/example; encoding=UTF-8'})
-        httputils.change_content_type(reply, {'image/example': 'image/jpeg'})
-        self.assertEqual(reply.headers['Content-Type'],
-                         'image/jpeg; encoding=UTF-8')
-
-    def test_wrong_mapping(self):
-        """Test with a mapping which doesn't match the header."""
-        reply = FakeNetworkReply(headers={'Content-Type': 'image/example'})
-        httputils.change_content_type(reply, {'image/foo': 'image/bar'})
-        self.assertEqual(reply.headers['Content-Type'], 'image/example')
-
-    def test_empty_mapping(self):
-        """Test with a mapping which is empty."""
-        reply = FakeNetworkReply(headers={'Content-Type': 'image/example'})
-        httputils.change_content_type(reply, {})
-        self.assertEqual(reply.headers['Content-Type'], 'image/example')
-
-
 if __name__ == '__main__':
     unittest.main()
diff --git a/qutebrowser/utils/http.py b/qutebrowser/utils/http.py
index d7d2f17f9..91a6c9173 100644
--- a/qutebrowser/utils/http.py
+++ b/qutebrowser/utils/http.py
@@ -84,27 +84,3 @@ def parse_content_type(reply):
         ret = [content_type, None]
     ret[0] = ret[0].strip()
     return ret
-
-
-def change_content_type(reply, mapping):
-    """Change a content-type of a QNetworkReply.
-
-    Args:
-        reply: The QNetworkReply to handle.
-        mapping: A mapping of source to target content types.
-
-    Return:
-        None (modifies the passed reply).
-    """
-    content_type, rest = parse_content_type(reply)
-    if content_type is None:
-        return
-    try:
-        content_type = mapping[content_type]
-    except KeyError:
-        return
-    if rest is not None:
-        header = ';'.join((content_type, rest))
-    else:
-        header = content_type
-    reply.setHeader(QNetworkRequest.ContentTypeHeader, header)