I used a solution which is also not that great, but at least one don’t have to alter the core files.

create an array and store the added code in it, then every time before calling the script object first check if it was already added.

Something like this:

if(!in_array($jsCode, $this->inlineScriptBugFixArray)){

        $scripts->headScript('SCRIPT', $jsCode);
	$this->inlineScriptBugFixArray[]=$jsCode;
}

and the above will obviously be inside a method that can be called every time a script needs to be added, ensuring its unique everytime, at the cost of some memory for storing $jsCode in the array.