Tab-Enabled
This property specifies whether the page identified by the 
Tab-Index property can be selected by the user or not. A value of 0 means that the page is disabled, so clicking on that page will produce no effects. A value of 1 means that the page is enabled, so the user can select it. Each page is enabled by default.
 
Example - Modify a Ribbon control to disable the third page
procedure division. ...   modify screen-1-rbn-1-hdl tab-index 3 tab-enabled 0 ...  |