Hello Bryan Drennen,
When you dock a sliding pane, its parent RadPane control resizes, so that the whole sliding pane is visible. The pane additionally preserves its size across postbacks. As a result, even though you undock the sliding pane, you do not set the size of the parent pane back to 22px and the pane preserves its size as it was before the postback, when you had a docked sliding pane. That is why, I would recommend that you set the Width of the parent RadPane control of the sliding pane back to 22px, when you undock the sliding pane.
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