Firefox Portable and registry keys for Native Messaging

Hello,

I'm trying to use an addon called Scrapbee with Firefox portable v71.

This addon uses the Native Messaging Hosts parameters to refer a JSON. On Windows, this is usually done through the registry with the following keys :
- HKEY_LOCAL_MACHINE\SOFTWARE\Mozilla\NativeMessagingHosts\scrapbee_backend
- HKEY_CURRENT_USER\Software\Mozilla\NativeMessagingHosts\scrapbee_backend

Is there a way to automatically create those temporary keys? I looked to some settings like [RegistryKeys] and other parameters explained on https://portableapps.com/manuals/PortableApps.comLauncher/ref/launcher.i... but it's not really clear on where those parameters should be added.

The \App\AppInfo\ folder for Firefox has no "Launcher" directory (whereas OperaPortable has one for example), so :
- Should I create the directory and create a FirefoxPortable.ini in the new directory?
or
- Should I use \Data\settings\FirefoxPortableSettings.ini for that

Does someone has a sample code for this? (to create the key, then cleanup on closing)

regards,
Fred