manual/include/track-height.html

<p>
  Depending on the stage of your production, you may require a quick
  overview over as many tracks as possible, a detailed view into just a
  few, or a combination of the two. To facilitate this, the
  <dfn>height</dfn> may be configured individually for each track in
  the editor window.
</p>
<p>
  A context click on a track header will display the
  <kbd class="menu">Height</kbd> menu, and allow you to choose from a
  list of standard sizes. All selected tracks will be redrawn using that
  height.
</p>
<p>
  Alternatively, select the tracks you wish to resize. Move the pointer
  to the bottom edge of one track header. The cursor will change to a
  two-way vertical arrow shape. <kbd class="mouse">Left</kbd>-drag to
  dynamically resize all selected tracks.
</p>
<h2>Fit to the Editor Window</h2>
<p>
  Select the tracks you wish to display in the Editor window.
  Choose <kbd class="menu">Track &gt; Height &gt; Fit Selected Tracks</kbd>
  or use the keyboard shortcut, <kbd>f</kbd>. Ardour adjusts the track
  heights and view so that the selected tracks completely fill the vertical
  space available, unless the tracks cannot be fitted even at the smallest
  possible size.
</p>
<p class="note">
  You can use <dfn>Visual Undo</dfn> (default shortcut: <kbd class="mod3">Z</kbd>
  to revert this operation.
</p>