Adding Autoload/singleton in Runtime from script

[ripperdave]

Godot version

3.3.3

System information

Windows 10

Issue description

I am working on a game collection launcher. I have 10 existing games with Autoloaded singletons. I plan to add more in future.
I import existing games through .pck (ProjectSettings.load_resource_pack(...)), but imported games need their own singletons.

1, How can I add autoload singletons after the game (collection launcher) started?
Adding nodes to root won't make the node visible in global scope variables. (cannot access the singleton by its name)
2, Is there any way to add global scope variables?

No details about this in documents:
(https://docs.godotengine.org/en/stable/getting_started/workflow/export/exporting_pcks.html?#summary)
https://docs.godotengine.org/en/stable/getting_started/step_by_step/singletons_autoload.html

Thanks.

Steps to reproduce

Try to add autoload singleton after the game is started.

Minimal reproduction project

No response

[Calinou]

Please don't ask support questions here, as this issue tracker is meant to be used for bug reports only. Use one of the other community channels instead.

I import existing games through .pck (ProjectSettings.load_resource_pack(...)), but imported games need their own singletons.

If the games are entirely separate, they should not be using singletons (or they should be separate processes if the platform allows this). It's an architecture decision you need to make here, but it's entirely feasible.