BILL_601 I found it didn't really work for me. It would disable the printed functions on the keys, but they wouldn't work as actual functions keys.
Just wondering what file in the OS this alters. Ever since I uninstalled it, my keyboard and trackpad will quit working. I can use a bluetooth mouse and I can use the Keyboard Viewer. I can even Share Screen from another computer, but the local keyboard and trackpad won't work until I put the thing to sleep and wake it up again. That seems to fix it for a little while.
Perhaps the developer can comment on what file may be affected to cause this?
(Version 1.3)