This web page displays the text content of itself in the top
right pane and its DOM structure in the left pane.
The DOM structure is a Composite structure consisting of
various kinds of HTML elements, Comment elements, and Text
elements.
The level of indentation indicates the hierarchical structure.
When you click on an element in the left pane some information
will be displayed in the bottom right pane.
For an HTMLElement, its innerHTML attribute is displayed.
For a Comment or a Text element, its data attribute is displayed.
Note that the comment at the top of the web page is moved into
the element for the head tag.
Many of the Text elements contain nothing but white space.
Much of the innerHTML attribute for the HTMLBodyElement is not
present in the original document.
It results from elements added by the JavaScript code that
produces the three panes that you are viewing.
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A DOM Structure Example