The Position and size dialog for formatting a chart (right-click on chart and select Position and Size) includes a section called Adapt. Under this, there are options to Fit width to text and Fit height to text. Both options are grayed out.
From other posts, it appears that the grayed out options are really for text boxes, not charts. Is that correct? If so, what can be done to remove those options on dialogs where they are not relevant?