Variable dropdown for unofficial extensions?

[RixInGithub]

Hello, scratch-vm developers. I have come here a long time ago to get help on my RixxyX project, however, I request help for a secret newer extension I'm making.

I want to have a block that has a variable dropdown, something similar to the set [var v] to [value] block.

I have created a makeshift dropdown that lists the current sprite's variables, however it doesnt have the fancy "Rename variable" or "Delete variable" options. Sure, I could probably add those in, but the reason I said "probably" is because I have no idea how to trigger the actual things it does and then force the dropdown input to read a different value.

EDIT: here's the makeshift dropdown code (sorry, i have the tendency to golf my code in a way that it doesnt have spaces, hence the Reflect.construct(...) (yes, i know, i could have used null or something like it))

		getVars(targetId){ // note: only works when unsandboxed
			var idfk1 = function(a){return(Scratch.vm.runtime.targets.find)(a).variables}
			return(Object).entries(Object.assign(idfk1(function(a){return(a.id)==targetId}),idfk1(function(a){return(a.isStage)}))).map(function([_,{name}]){return""+name}).sort(function(a,b){return(a.toLowerCase()<b.toLowerCase())?-1:((a.toLowerCase()<b.toLowerCase())?0:Reflect.construct(Function,[""])())})
		}