Single Expand Palettes (Magic xpa 3.x)
When set to No, you can have all the sections of the property sheet expanded at the same time.
When set to Yes, only one section in the property sheet can be expanded. Expanding a collapsed section collapses the currently expanded section.
Exception: This functionality is not supported for the Visual Studio-based Form Designer.
Available values: Yes, No
Default: No
Change Effective: Immediate
Magic.ini and Command Line name: SingleExpandPalettes
How Do I Keep the Property Sheet Showing a Single Section at a Time?