/usr/share/cairo-dock/plug-ins/rendering/readme-rainbow-view is in cairo-dock-plug-ins-data 3.3.99.beta1.2.really.3.3.2-0ubuntu2.
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1 2 3 | <b>Rainbow view</b>
An original view, designed for sub-docks with few icons.
Icons' labels can be displayed horizontally or not.
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