Whether or not the connection should be automatically connected by NetworkManager when the resources for the connection are available.
true to automatically activate the connection, false to require manual intervention to activate the connection.
Autoconnect happens when the circumstances are suitable. That means for example that the device is currently managed and not active. Autoconnect thus never replaces or competes with an already active profile.
Note that autoconnect is not implemented for VPN profiles. See secondaries as an alternative to automatically connect VPN profiles.
If multiple profiles are ready to autoconnect on the same device, the one with the better "connection.autoconnect-priority" is chosen. If the priorities are equal, then the most recently connected profile is activated. If the profiles were not connected earlier or their "connection.timestamp" is identical, the choice is undefined.
Depending on "connection.multi-connect", a profile can (auto)connect only once at a time or multiple times.