Represents the pane tabs in the HTML editor.
Assembly: EnvDTE90 (in EnvDTE90.dll)
Visual Studio 2008 adds a Split view to the Source and Design views in the HTML editor. Split view separates the tab and view elements of the HTML edit window. Switching the view (to either Design or Source) does not necessarily mean switching the tab (Design/Split/Source). For example, when you click the Split tab, switching views between Design and Source does not change the tab, it only activates or deactivates the Design and Source panes in the Split view. This enumeration represents the three tabs in the HTML editor.