clarification of pTM/ipTM scores in AF multimer

Hello, reading the AF multimer manuscript I see ipTM reflects on all inter-chain confidence. However, it is not clear to me if pTM is computed on all residues, or only on same-chain residues, as this is not really made clear in the manuscript. In the monomer model the two things are one and the same, but I wonder if in multimer pTM is onlz based on intra-chain confidence or it is all-residue?