diff --git a/mitmproxy/types/multidict.py b/mitmproxy/types/multidict.py
index 0a9b12d9e..c4f42580d 100644
--- a/mitmproxy/types/multidict.py
+++ b/mitmproxy/types/multidict.py
@@ -4,7 +4,7 @@ from collections.abc import MutableMapping
 from mitmproxy.types import serializable
 
 
-class _MultiDict(MutableMapping, serializable.Serializable, metaclass=ABCMeta):
+class _MultiDict(MutableMapping, metaclass=ABCMeta):
     def __repr__(self):
         fields = (
             repr(field)
@@ -171,18 +171,8 @@ class _MultiDict(MutableMapping, serializable.Serializable, metaclass=ABCMeta):
                 coll.append([key, values])
         return coll
 
-    def get_state(self):
-        return self.fields
 
-    def set_state(self, state):
-        self.fields = tuple(tuple(x) for x in state)
-
-    @classmethod
-    def from_state(cls, state):
-        return cls(state)
-
-
-class MultiDict(_MultiDict):
+class MultiDict(_MultiDict, serializable.Serializable):
     def __init__(self, fields=()):
         super().__init__()
         self.fields = tuple(
@@ -197,6 +187,16 @@ class MultiDict(_MultiDict):
     def _kconv(key):
         return key
 
+    def get_state(self):
+        return self.fields
+
+    def set_state(self, state):
+        self.fields = tuple(tuple(x) for x in state)
+
+    @classmethod
+    def from_state(cls, state):
+        return cls(state)
+
 
 class MultiDictView(_MultiDict):
     """
@@ -227,3 +227,6 @@ class MultiDictView(_MultiDict):
     @fields.setter
     def fields(self, value):
         self._setter(value)
+
+    def copy(self):
+        return MultiDict(self.fields)
diff --git a/test/mitmproxy/types/test_multidict.py b/test/mitmproxy/types/test_multidict.py
index 3b879ed16..c76cd7537 100644
--- a/test/mitmproxy/types/test_multidict.py
+++ b/test/mitmproxy/types/test_multidict.py
@@ -200,3 +200,12 @@ class TestMultiDictView:
         tv["c"] = "b"
         assert p.vals == (("a", "b"), ("c", "b"))
         assert tv["a"] == "b"
+
+    def test_copy(self):
+        p = TParent()
+        tv = multidict.MultiDictView(p.getter, p.setter)
+        c = tv.copy()
+        assert isinstance(c, multidict.MultiDict)
+        assert tv.items() == c.items()
+        c["foo"] = "bar"
+        assert tv.items() != c.items()