Update to 3.11.2 broke my DHCP

Software SW help
19

When executing /etc/init.d/dnsmasq restart I get these errors. I have another DCHP server running on my lan and DHCP switched off in the configuration of the networks.

2019-04-02 10:16:24 notice dnsmasq[]: DNS rebinding protection is active, will discard upstream RFC1918 responses!
2019-04-02 10:16:24 notice dnsmasq[]: Allowing 127.0.0.0/8 responses
2019-04-02 10:16:24 crit dnsmasq[11388]: failed to create listening socket for port 53: Address in use
2019-04-02 10:16:24 crit dnsmasq[11388]: FAILED to start up
2019-04-02 10:16:34 notice dnsmasq[]: DNS rebinding protection is active, will discard upstream RFC1918 responses!
2019-04-02 10:16:34 notice dnsmasq[]: Allowing 127.0.0.0/8 responses
2019-04-02 10:16:34 crit dnsmasq[11571]: failed to create listening socket for port 53: Address in use
2019-04-02 10:16:34 crit dnsmasq[11571]: FAILED to start up

Some other program is sitting on the port 53, but which one?

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