Plugin access to user defined variables

[Timoses]

Is your feature request related to a problem? Please describe.
I noticed that VariableManager.ListVariables is marked as obsolete.
I suppose the idea behind this is that plugins should only use their own Variables. However, it may be desirable for some plugins to have access to user defined variables.

Describe the solution you'd like
The easiest would be to rather than limiting plugin variable scope allow plugins to access all variables.

To protect certain variables, it could be possible to allow the user to mark a variable as "secret".

Additionally, or alternatively, the user could select which plugins shall have access to a variable.

Describe alternatives you've considered
I can only speculate on the motivation of deprecating 'ListVariables'. Above solution propositions probably reflect this.

Additional context
In my use case I would like to have User-defined variables and use those in an AHK-Plugin Script.