the-last-browser-launcher/lib/launch/opera-prefs.json

Detect, launch and stop browsers

{
	"browser": {
		"check_default_browser": false
	},
	"profile": {
		"content_settings": {
			"clear_on_exit_migrated": true
		},
		"default_content_settings": {
			"popups": 1
		},
		"password_manager_enabled": false
	},
	"session": {
		"restore_on_startup": 5
	},
	"statistics": {
		"collection_asked": true,
		"collection_enabled": false
	}
}