>>214602220 (OP)
In the end, the Hungarians agreed to this, there was even a celebration and a parade in Zagreb, but it was too late: a few days later, the Croatian parliament declared the severance of all ties with Austria and Hungary and declared the State of Slovenes, Croats and Serbs, which united with Serbia and Montenegro a month later. The Danube Monarchy was better for us than Yugoslavia, but that does not make it good per se. An independent Croatia is the only real option. We have remained friends with the countries of the Monarchy, and are even part of a common military alliance.
https://en.m.wikipedia.org/wiki/Central_European_Defence_Cooperation