I am running the newest version of Modelio (5.4) and cannot for the life of me figure out how to reorder attributes within a class on a class diagram. It's simply for readability, but it would be very useful to know how to reorder them without just having to remake the class as suggested here (Rearranging attributes in Modelio) or deleting the class and remaking it in a different order. Honestly this seems like it should be a pretty straightforward thing to do, but I can't find anything about it in their official docs. The closest I've found was the thread linked above, neither the answer given nor the suggested github thread worked for me.
I posted this question to Modelio's forums and a user there was able to answer the question:
Select the class;
Go to symbol view;
Set the automatic content on manual;
In explorer move the operation/attributes as you wish using the move up/down arrows.