Fix: T49025 ivy gen invoke thanks @batfinger

add_curve_ivygen.py

@@ -538,6 +538,10 @@ class IvyGen(bpy.types.Operator):
                 (ob.type == 'MESH') and
                 (context.mode == 'OBJECT'))
         
+    def invoke(self, context, event):
+        self.updateIvy = True
+        return self.execute(context)
+
     def execute(self, context):
         if not self.updateIvy:
             return {'PASS_THROUGH'}