Syntax check failure

  • I notice that when I paste the following XUL content into a xul file, the syntax checker finds a problem with the toolbox element ("cvc-complex-type.2.4.b: The content of element 'toolbox' is not complete. One of [snip] expected"). This content is drawn from the Mozilla XUL tutorials ( I'm a little confused by the error message, because it suggests a large number of elements that could be included in a toolbox, but adding an arbitrary one doesn't necessarily resolve the error. Am I mis-understanding, or is this tutorial code sample now incorrect with the XUL spec?

    <?xml version="1.0"?>
    <?xml-stylesheet href="chrome://global/skin/" type="text/css"?>
    <window id="example-window" title="Example 5.2.1"
    <toolbox flex="1">
      <menubar id="sample-menubar">
        <menu id="file-menu" label="File">
          <menupopup id="file-popup">
            <menuitem label="New"/>
            <menuitem label="Open"/>
            <menuitem label="Save"/>
            <menuitem label="Exit"/>

    Thanks -- Dennis