My Fiance and I were really happy to see that it was possible to eat vegan in Croatia, and still enjoy the local cuisine.
To be honest, the Croatians do cook meat heavy - however, there are so many things they do offer and make really delicious that we were never put out.
Salads are incredible there.
There are a lot of 'side dishes' that are offered in most restaurants that are incredible.
In our opinion, it was very do-able and enjoyable.
Hope that helps!