Run MutationObserver

[boo-code]

I try to use global variables in JS code for MutationObserver, but these variables are not accessible once JS block execution is finished. Code bellow. E.g. window.runing is not accessible in whileloop block. Is there any solution in Automa for global JS variables and execution of MutationObserver in a page?

obj = document.querySelector('textarea~button div');
window.runing = false;

window.observer = new MutationObserver(function(mutations) {    
	mutations.forEach(function(mutation) {
		window.runing = !window.runing;
  });    
});

// start monitoring the changes
window.observer.observe(obj, {attributes: true, childList: true, subtree: true, characterData: true});