diff --git a/testing/mozbase/mozproxy/mozproxy/backends/mitm/manifests/mitmproxy-rel-bin-6.0.2-linux64.manifest b/testing/mozbase/mozproxy/mozproxy/backends/mitm/manifests/mitmproxy-rel-bin-6.0.2-linux64.manifest
new file mode 100644
index 000000000000..fcdb65c9b740
--- /dev/null
+++ b/testing/mozbase/mozproxy/mozproxy/backends/mitm/manifests/mitmproxy-rel-bin-6.0.2-linux64.manifest
@@ -0,0 +1,10 @@
+[
+    {
+    "filename": "mitmproxy-6.0.2-linux.tar.gz",
+    "size": 73691215,
+    "algorithm": "sha512",
+    "digest": "e7cbcdee1eda9f7c9ea9b6c811930a7b21403f52b24a1f14030a69a4ee62dd6bf9fa5a0a9f8acc44830803da27b856f0900a09fd560b32384ab2c0e78a1d08ad",
+    "visibility": "public",
+    "unpack": true
+    }
+]
diff --git a/testing/mozbase/mozproxy/mozproxy/backends/mitm/manifests/mitmproxy-rel-bin-6.0.2-osx.manifest b/testing/mozbase/mozproxy/mozproxy/backends/mitm/manifests/mitmproxy-rel-bin-6.0.2-osx.manifest
new file mode 100644
index 000000000000..5e48ba3405b1
--- /dev/null
+++ b/testing/mozbase/mozproxy/mozproxy/backends/mitm/manifests/mitmproxy-rel-bin-6.0.2-osx.manifest
@@ -0,0 +1,10 @@
+[
+  {
+    "filename": "mitmproxy-6.0.2-osx.tar.gz",
+    "size": 40867811,
+    "algorithm": "sha512",
+    "digest": "f162e89073eb73f7cfe458d54157e31e9e6bb7ae42c262e4070d23949888630015c896de8870958e83ad9360fce6758f01813ce581cb1a3c1a8b436109d2f28d",
+    "visibility": "public",
+    "unpack": true
+  }
+]
diff --git a/testing/mozbase/mozproxy/mozproxy/backends/mitm/manifests/mitmproxy-rel-bin-6.0.2-win.manifest b/testing/mozbase/mozproxy/mozproxy/backends/mitm/manifests/mitmproxy-rel-bin-6.0.2-win.manifest
new file mode 100644
index 000000000000..e5060cbf2829
--- /dev/null
+++ b/testing/mozbase/mozproxy/mozproxy/backends/mitm/manifests/mitmproxy-rel-bin-6.0.2-win.manifest
@@ -0,0 +1,10 @@
+[
+  {
+    "filename": "mitmproxy-6.0.2-windows.zip",
+    "size": 36482912,
+    "algorithm": "sha512",
+    "digest": "242701b5090fe71526ac887843ca08a674a5b1261c21f9f8cb86d143b16b4bc50fca80b016b140a4c0fd2c6ec5819aee1e145a57b000a293fe290ba1b21bac9f",
+    "visibility": "public",
+    "unpack": true
+  }
+]
diff --git a/testing/mozbase/mozproxy/mozproxy/backends/mitm/mitm.py b/testing/mozbase/mozproxy/mozproxy/backends/mitm/mitm.py
index 15d206eb7e31..99c62fa3292a 100644
--- a/testing/mozbase/mozproxy/mozproxy/backends/mitm/mitm.py
+++ b/testing/mozbase/mozproxy/mozproxy/backends/mitm/mitm.py
@@ -310,7 +310,7 @@ class Mitmproxy(Playback):
                     "alternate-server-replay.py",
                 )
 
-                if self.config["playback_version"] in ["4.0.4", "5.1.1"]:
+                if self.config["playback_version"] in ["4.0.4", "5.1.1", "6.0.2"]:
                     args = [
                         "-v",  # Verbose mode
                         "--set",
diff --git a/testing/mozbase/mozproxy/mozproxy/backends/mitm/scripts/alternate-server-replay.py b/testing/mozbase/mozproxy/mozproxy/backends/mitm/scripts/alternate-server-replay.py
index 2fe64a66a767..bfe44a5edef6 100644
--- a/testing/mozbase/mozproxy/mozproxy/backends/mitm/scripts/alternate-server-replay.py
+++ b/testing/mozbase/mozproxy/mozproxy/backends/mitm/scripts/alternate-server-replay.py
@@ -126,7 +126,12 @@ class AlternateServerPlayback:
                     "Recorded response is a WebSocketFlow. Removing from recording list as"
                     "  WebSockets are disabled"
                 )
-            elif i.response and self.mitm_version in ("4.0.2", "4.0.4", "5.1.1"):
+            elif i.response and self.mitm_version in (
+                "4.0.2",
+                "4.0.4",
+                "5.1.1",
+                "6.0.2",
+            ):
                 # see: https://github.com/mitmproxy/mitmproxy/issues/3856
                 f = self.flowmap.setdefault(
                     self._hash(i), {"flow": None, "reply_count": 0}