It's surprising that using a non-standard listening port will cause peers to actively avoid connecting to you, is it sensible to add this to the help message and the warnings on startup if people have changed the default? I can't find this behavior mentioned anywhere except for the comments in net.cpp. 

```
// do not allow non-default ports, unless after 50 invalid addresses selected already
if (addr.GetPort() != Params().GetDefaultPort() && nTries < 50)
continue;
```

https://github.com/bitcoin/bitcoin/blob/master/src/net.cpp#L1369

if (addrman.size() == 0 && (GetTime() - nStart > 60)) {
            static bool done = false;
            if (!done) {
                LogPrintf("Adding fixed seed nodes as DNS doesn't seem to be available.\n");
                CNetAddr local;
                local.SetInternal("fixedseeds");
                addrman.Add(convertSeed6(Params().FixedSeeds()), local);
                done = true;
            }
        }
        
        
        
        CAddress addrConnect;
        
        int nOutboundFullRelay = 0;
        int nOutboundBlockRelay = 0;
        std::set<std::vector<unsigned char> > setConnected;
        {
            LOCK(cs_vNodes);
            for (const CNode* pnode : vNodes) {
                if (pnode->IsFullOutboundConn()) nOutboundFullRelay++;
                if (pnode->IsBlockOnlyConn()) nOutboundBlockRelay++;
                
                
                
                
                
                switch (pnode->m_conn_type) {