I’m not sure if it’s exactly what you want but here is an example:
This is the code that is in the Button Widget:
You check if the Menu Widget is valid (existing or not), if not then we create it, set the variable to it and then add it to the viewport. If it does exist, we remove it from the parent (it’s like DestroyActor for actors) and then we set the variable with no input, it’s like if we are emptying it.