RetroCore prints warnings if destroyed after its keyboard widgets
(retro-demo:3): GLib-GObject-WARNING **: 15:06:44.274: ../gobject/gsignal.c:2735: instance '0x55a1463e5340' has no handler with id '82'
(retro-demo:3): GLib-GObject-WARNING **: 15:06:44.274: ../gobject/gsignal.c:2735: instance '0x55a1463e5340' has no handler with id '83'
The problem is that we use g_signal_connect_object()
to connect those handlers, and if the keyboard is already destroyed when we want to disconnect them, we disconnect them anyway even though they have been already disconnected automatically.