Cannot bootstrap GNUnet 0.21.0

Hi all,

I've just built and installed the new GNUnet 0.21. But my node isn't connec=
ted to any peer after hours of waiting. Running gnunet-core shows no node i=
s connected to me.

```
=E2=9D=AF gnunet-core
(no output)
```

I have also checked `iotop` and can confirm gnunet-service-transport isn't =
doing much IO. While I was expecting at least hundreds of Kbps from experie=
nce in the past.

How can I connect to the network? Please let me know what information I can=
 provide to diagnose the issue.

Best,
Martin