Question

I am trying to update the css attribute for a toolbarbutton but the following does not work:

document.getElementById('toolbar-button').style.listStyleImage = url("chrome://ext/skin/toolbar-button-add.png");

Answer 1

Is that line of code you posted directly copy and pasted from your code?

Because if it is, you are missing the ' around the value. It should be

document.getElementById('toolbar-button').style.listStyleImage = 'url("chrome://ext/skin/toolbar-button-add.png")';

Always watch the debug console as this would have been revealed in the console as something like 'url': is not a function or something like that.