Disconnects while connected through VPN

[agners]

I am using Wireguard as a VPN. Wireguard uses UDP and reconnects automatically, TCP connections through it usually stay alive. However, when using ConnectBot connections get disconnected when roaming from WiFi to 4G. This seems to be caused by ConnectBot itself. The ConnectivityManager reports for a short period that there is no connectivity, which causes ConnectBot to kill all connections:

07-05 01:07:09.438 13773 13773 D CB.ConnectivityManager: onReceived() called; noConnectivity? true; isFailover? false
07-05 01:07:09.483 13773 13773 D CB.ConnectivityManager: onReceived() called; noConnectivity? false; isFailover? false

Android nowadays uses SOCK_DESTROY to close sockets depending on which interface the TCP has been useing. It seems that manual handling as it is used in ConnectBot is not ideal and no longer necessary.