@benji7000 

The only thing i can think off is that question ID can be different in other surveys.

@benji7000 Please check how the question is set up in your other survey. Is it specified with exactly the same details? 

The only issue I see is this part: 

jQuery("#question-"+this.questionId+" textarea") 

Usually the IDs do not start with “question” but rather looks like this:

You can check the developer tools of your browser (usually F12) to find out the ID of the text area and then do something like:

var textarea = document.getElementById("myTextareaId");

If you only have one textarea HTML element on the page, you can also use (takes the first textarea element on the page):

var textarea = document.querySelector("textarea");

Putting everything together… Try this: 

Qualtrics.SurveyEngine.addOnload(function()
{
    /*Place your JavaScript here to run when the page loads*/

});


Qualtrics.SurveyEngine.addOnReady(function() {

    var text_placeholder = 'Good things or people you can feel grateful about, and why.'
	var textarea = document.querySelector("textarea");
	if (textarea) {
		textarea.setAttribute("placeholder", text_placeholder);
	}

   //  jQuery("#question-"+this.questionId+" textarea").attr("placeholder", text_placeholder);

});

Qualtrics.SurveyEngine.addOnUnload(function()
{
    /*Place your JavaScript here to run when the page is unloaded*/

});

For me it correctly sets the placeholder:

Best
Christian

The below should work for all layouts other than the simple

Qualtrics.SurveyEngine.addOnReady(function()
{
	/*Place your JavaScript here to run when the page is fully displayed*/
  var text_placeholder = 'Good things or people you can feel grateful about, and why.'

    jQuery("#"+this.questionId+" .InputText").attr("placeholder", text_placeholder);
});