hfy-link-extn

hfy-link-extn is a variable defined in `htmlfontify.el'.
Its value is

nil

Documentation:
File extension used for href links.
Useful where the htmlfontify output files are going to be processed
again, with a resulting change in file extension. If nil, then any
code using this should fall back to `hfy-extn'.

You can customize this variable.