Currently when geary opened using Desktop Actions from dock it will show you geary's message list with embeded composer widget. it will be good if when geary being called with mailto argument, it only show composer window without the message list
the reason is when user open using "Compose message" Actions, its most likely they want to quickly create a message without the need to read other email. i will feels more focused on writing and not distracted with message list below.
Thanks