Beginner Question on Modifying Text w/ Greasemonkey

[DaveyJake]

JavaScript has always haunted me as a language. I know HTML and CSS but JS always ruins me!

I'm trying to write a very simple, very basic script just to see if I can get the hang of it. I'm trying to tweak the appearance of my Gmail address inside my inbox.

Instead having my address being displayed as firstlast@gmail.com, I would rather have it as first.last@gmail.com. Here's is my code:

(function () {
	
	var newEmail = "first.last@gmail.com";
	var nameTag = document.getElementsByTagName('span').getElementById('gbi4t')[0];
	nameTag.setAttribute(innerHTML, newEmail);

}) ();

I just can't seem to get it to work. What am I doing wrong?

[LRM]

First, each ID name should only ever be defined/used once on a page.

Next:
getElementsByTagName() returns an array of pointers, accessible numerically through an array reference [#] tacked on at the end like this: getElementsByTagName()[0].

getElementById() returns a single pointer (which is one reason why an ID name should only be used once on a page - your script won't know which one you mean).

So far, it appears your script is backwards and should probably be:
var nameTag = document.getElementById('gbi4t').getElementsByTagName('span')[0];

Since I can't imagine gMail using improper coding, if the span containing the email address you want to change has the id gbi4t this is probably all you need.
var nameTag = document.getElementById('gbi4t');

If it is the first span inside of a container that has the id gbi4t its as I pointed out above:
var nameTag = document.getElementById('gbi4t').getElementsByTagName('span')[0];


I'm just guessing here since I don't know exactly what you are trying to reference.