The NoFollow Plugin is broken when it comes to whitelisting. The fix is very simple…
What causes the plugin to break:
Note also, the fetch_param() function has been changed so that parameter values of ‘y’, ‘on’ and ‘yes’ all return ‘yes’, while ‘n’, ‘off’ and ‘no’ all return ‘no’. Your module or plugin may need to be changed accordingly.
So all you have to do is change those ‘y’ & ‘n’ instances to ‘yes’ and ‘no’, then it works again.