How to set global custom variable from local variable?

[Nodi-Rubrum]

How to set global custom variable from local variable? Given the 'new' way to subscribe to MQTT topics, forces you to use a local variable (per the notice that MQTT payload value set direct to global variable is going to be depreciated). I am now puzzled as to how to get the local variable value into a global variable.

[Julusian]

(copied from the other discussion)

Its not pretty, but you can get that feedback into a global variable through an expression variable. It is a bit tedious as you will need to add the local variable and set the expression to reference that variable, but would work.

An earlier iteration of expression variables was to allow any feedback type to be chosen, but it was deemed too confusing/complex to handle all the different cases in a good UX