As an improvement, we wish to add a hashed customer number as a url parameter to the URL.
Can someone provide a solution on how to add the cryptedAccountId to each URL?
Try the documented jsapi cryptString() function on account id, add cryptedAccountId to all your personalization, or batch select cryptedAccountId's in the script (expensive).
NB there are several undocumented encryption functions so cryptString() may not match the computed col's xtk AESEncrypt() call.
Another avenue is to alter tracking calculation click formula instead of writing a control typology here, if possible for your use case.
In addition of what Jon wodnicki mentions, you must also escape the result for URL compliance.
We manages to add the Recipient Id field using the formula of the Web analytics External Account. It's not a typology rule, but it works well to add any recipient field on any url.
Demo, we land on this URL when we click on a link in the email: