diff --git a/libp2p/security/noise/io.py b/libp2p/security/noise/io.py
index 877aa5ab..a24b6c74 100644
--- a/libp2p/security/noise/io.py
+++ b/libp2p/security/noise/io.py
@@ -41,7 +41,8 @@ class BaseNoiseMsgReadWriter(EncryptedMsgReadWriter):
     read_writer: NoisePacketReadWriter
     noise_state: NoiseState
 
-    # FIXME: This prefix is added in msg#3 in Go. Check whether it's a desired behavior.
+    # NOTE: This prefix is added in msg#3 in Go.
+    #       Support in py-libp2p is available but not used
     prefix: bytes = b"\x00" * 32
 
     def __init__(self, conn: IRawConnection, noise_state: NoiseState) -> None:
diff --git a/newsfragments/592.internal.rst b/newsfragments/592.internal.rst
new file mode 100644
index 00000000..6450be85
--- /dev/null
+++ b/newsfragments/592.internal.rst
@@ -0,0 +1 @@
+remove FIXME comment since it's obsolete and 32-byte prefix support is there but not enabled by default