No indication in the logs, but all is well after that change.

Ran longer with those settings, but eventually crashed the browser again and would not reload.
Port 8081 is open on the host and it detects motion and sends email.

In fact it's not dead - motion triggered an email and I was able to connect with the browser again.
Control was set to logalhost, so that made sense.
I set stream motion to on to see if that helps with the browser reconnecting when no motion has been detected for a long period of time.

Fresh rasberian installation, motion-mmalcam will run properly for an hour or so, then crash firefox.
If I reconnect I get one still which will not refresh. If I refresh the browser - nothing. Can't connect on 8080 either.
I can see the process running and using about 20% CPU