Link to import-im6.q16 not allowed by security policy ?

[Roger Price <debian@rogerprice.org>]

I use the import program provided by Debian 11 (bullseye) to grab parts of the 
screen.  This worked well but I was having difficulty remembering that "import" 
means "screen-grab".  So as root I set up the soft link

 ln -s /usr/bin/import /usr/bin/screen-grab

Now, whenever I try to run screen-grab or import or import-im6.q16 I get the 
error message:

 import-im6.q16: attempt to perform an operation not allowed by the security
 policy `PS' @ error/constitute.c/IsCoderAuthorized/421.

So I removed the link, but calls to import still produce the error message.

How can I get back to the original behaviour?  Where should I start 
looking?

Roger