Hi Jacob,
as we do not use JMS messages in our BPM I cannot tell much about that.
We are still using native pub/sub with Broker currently in 9.12.
Did you check the Administering Process Engine Guide if there is additional information?
I just checked a 9.5 version of this guide and it mentions that custom aliases can only be used for the subscription trigger, but not for the transition trigger.
I have never heard of PE_TRANSACTIONAL_ALIAS, only of PE_NONTRANSACTIONAL_ALIAS.
The reason for using the PE_NONTRANSACTIONAL_ALIAS seems to be somewhat technical when jms messages are involved in BPMs.
Despite that, I do not get the use case behind that what you are trying.
Regards,
Holger
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