<p>
  Adding subsystems to the shelf can be done in two ways:
  <ol>
    <li>via the context menu on the shelf</li>
    <li>via the context menu on a subsystem</li>
  </ol>
</p>
<h2>Adding subsystems via the shelf</h2>
<p>
  To add one or more subsystems to the shelf from the current pipeline, do
  the following:
  <ol>
    <li>Select one or more subsystems on the current pipeline</li>
    <li>Right-click on a category in the shelf and choose 'Add selected subsystems'</li>
  </ol>
</p>

<h2>Adding subsystems via the subsystem context menu</h2>
<p>
  To add a particular subsystem to the shelf, do the following:
  <ol>
    <li>Select a category in the shelf</li>
    <li>Right-click on a subsystem on the current canvas and select 'Put on shelf'</li>
  </ol>
</p>

<h2>Using subsystems from the shelf</h2>
<p>
  Subsystems can be dragged from the shelf to the current pipeline. You can also
  right-click on a subsystem in the shelf and choose 'Add to pipeline'.
</p>
<p>
  Hovering the mouse over a subsystem in the shelf reveals some information about the subsystem:
</p>
<br>
<br>
  <img src="images/lwb_shelf_subsystem_tooltip.png" alt="Shelf subsystem tooltip" border="3">
<br>
<br>
<p>
  If you want to edit or rename a subsystem from the shelf, add it to a pipeline, then make the 
  required edits, then re-add the edited subsystem to the shelf. When satisfied, you can remove
  the old subsystem from the shelf by right-clicking on the subsystem and choosing 'Remove from shelf'.
</p>