Most of the time we could auto-connect the device when the app manager starts.
Filter on 86b7095e-2bd0-499e-a704-d00f2524aeef / PAUL STOP SETTING QA CONTACT TO THE DEVTOOLS COMPONENT'S WATCHERS EMAIL FOR BUGS YOU FILE :)
I don't think we want to do that anymore.
Actually, that's something I want even more with WebIDE as connecting now requires two clicks instead of just one! But I see that more like a "auto-reconnect" than a "auto-connect to the first connected device".
This was implemented in bug 1045660.