New Rules Engine - Item less than another item

i use OH3 with the new rules engine.
I use a normal trigger and send a command. No problem.

But how can i use in the grafic editor the “But only if”?
If i say Item less than value. It works because i can selected it.
But how can i say item less than another item?
I cant choose it in the “item condition”.

I try to use “script condition” with the line if (item < item2) but it dont work.

How can i create the command “item less than item2” in this editor?

I tried blockly in the Part of “But only if”. I need only a compare between zwei Items gut i dont cant create a simple “If” command. And i dont know what i have Set with the “If” command to use it right. Only Set a “True” to use it in
“But only if”?