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The tree nodes are expanded and collapsed using the small icons to the left of each node (these may vary in appearance depending on your workstation setup). The middle mouse button does not serve this function anymore!Alternatively, double-click on the node name.
At the top of the tree is a set of breadcrumbs, showing the hierarchy up to the currently-selected node. Clicking on a node in the breadcrumbs will select the node in the tree.
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