Is 45 min enough time to get from terminal 3 to terminal 1?
We are flying from Dubrovnik to Paris with one stop in Vienna.
Assuming this is on one ticket: All you will be doing is walk from one gate to another. No passport control or security. Vienna is very efficient.
In reality there is only one terminal. The distinction between terminal 1 and 3 is only important for passengers originating in Vienna.