Administration > Customizing Framesets > Customizing the Expand and Collapse Icons
  
Customizing the Expand and Collapse Icons
You can customize the expand and collapse icons in the Table of Contents by modifying or replacing the following files:
expanded.gif — Indicates that contents of heading are visible
collapsd.gif — Indicates that contents of heading are hidden
leaf.gif — Indicates lowest level subheading in a heading (for example, page with folded corner)
empty.gif — Acts as a place holder
These files are located at Arbortext-path\framesets\.
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The empty.gif file acts as a place holder to preserve indentation spacing for the last item in the Table of Contents. This applies to Netscape and Internet Explorer browsers prior to version 4. In later versions, indentation is controlled by viewer.css.