thumbnailDefaultWidth
This parameter sets the default width of thumbnails in the viewer. You can change the default width to fit more thumbnails in the visible area.
The thumbnailDefaultWidth parameter set the width of each thumbnail,
including the measurement of any borders defined by the theme.
The value for this parameter is in pixels. By default, the width is 184 pixels. The minimum value is 50 pixels, and the maximum value is 400 pixels.
Sample syntax
<param name="thumbnailDefaultWidth" value="50" />