For some ASCII terminal definitions, function keys above F24 are supported. When ExtendedPFKeys is "yes" or "true", the visual keyboard mapper will add the keys F25-F36 to the list of available keys to map. This enables up to 36 function keys to be defined and used.
Example:
<add key="ExtendedPFKeys" value="yes"/>
The above setting will add keys PF25 through PF36 to the drop-down list available for mapping keys.