See if this helps:
Option 1: Use the Back-End of your Site to read the cookie and pass some flag to the mboxcreate method during page load. This can be used in the TnT console for targeting. e.g.
mboxCreate('orderConfirmPage', parameter=true);
Then, when targeting, if you don't see the mbox parameter in the list, just add it, it should work.
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Option 2:
- You need to create a plugin-offer that reads the cookie values and stores the values or flags in the profile or user parameters of the mbox with mbox update. You assign this plugin to the desired mbox location.
- In the targeting options: Visitor Behavior -> YourProfileParameter -> Condition..