Text displays when adding task via Chrome but not in Firefox. Why?

Could be related to this issue with Firefox:

Firefox uses the property textContent instead of innerText.

For more information and a workaround, see this post on Treehouse: Firefox innerText undefined - Teacher's Note

As mentioned in the Teacher's Note referenced by Van Wilson, we can solve the issue for firefox as follows:

if (typeof editButton.innerText === "undefined")  {
  editButton.textContent = "Edit";
} else {
  editButton.innerText = "Edit";
}

But there are multiple instances where we need to do the same checking. So to make it DRY, we can create two functions. Like this:

var setText = function(elementName, text) {
  if (typeof elementName.innerText === "undefined") {
    elementName.textContent = text;
  } else {
    elementName.innerText = text;
  } 
}

var getText = function(elementName) {
  if (typeof elementName.innerText === "undefined") {
    return elementName.textContent;
  } else {
    return elementName.innerText;
  }     
}

Then, when we need to set text of an element, we can do that in the following way:

setText(label, taskString);
setText(editButton, "Edit");
setText(deleteButton, "Delete");

And, when we need to get text of an element, we can do that in the following way:

getText(label);

As an example of getting text, in the editTask function, we needed to get the the text of the label's text and assign it to editInput.value. We can do it like this:

editInput.value = getText(label);

Hope that will help someone facing same issue.

Placid