For example, in this tx 0x4ece50ae828f2a0f27f45d086e85a55e6284bff31a0a89daca9df4b1b1f5cb75 the name input is 8436.eth (it should have been just 8436, as the .eth is inferred).

This operates against a name that actually looks like [fb1d24d5dc41613d5b4874e6cccb06ecf442f6f1773c3771c4fcce1161985a18].eth
which results in a namehash of 0xfb1d24d5dc41613d5b4874e6cccb06ecf442f6f1773c3771c4fcce1161985a18
and the NameWrapper emits an event with the packet bytes of 08383433362E6574680365746800.
when ensjs#bytesToPacket sees these bytes, it returns a name of 8436.eth.eth, which is incorrect.

bytesToPacket(hexToBytes("0x08383433362E6574680365746800")) === '8436.eth.eth'

additional context is available in namehash/ensnode#36 (comment)