CB Paid Subscriptions

Confirmed original length limit used to be 1024. Same as "return" and "cancel_return", which are unchanged from 1024. Example notify_url as follows.

https://xxxxxxxxx/index.php?option=com_comprofiler&view=pluginclass&plugin=cbpaidsubscriptions&cbpgacctno=1&cbppdtback=e27b0e0af661ec4e69a2aa76266f1e55&cbpbasket=2026&do=gw&result=notify&cbpid=cbp5ca6052bc4bc8212274933&format=raw

cbppdtback is absolutely not needed and cbpid might also be safely removed. Removing both goes from 265 (htmlspecialchars encoded) to 181 length.

cbpid is needed so that can't be removed. This puts us at 265 to 217.

Removing &do=gw would remove another 10 characters as well. The case check for do handles NULL and "gw" value so removing it would result in NULL and for it to still function, but if this gets set by SEF it will break the URL. So this also is not safe to remove.

cbppdtback is being checked before resultNotification is called so it is indeed also being verified for IPNs and is also not safe to simply remove.

The cbppdtback check in PayPal is always forced to true so it is safe to remove for PayPal usage only.