Prop searchMethod triggers onChange when loaded

I found something funky, not sure if it is by design or is it bug. I have two similar sandboxes here:
https://codesandbox.io/s/0p5oppl88n
https://codesandbox.io/s/9o526528oy
Only difference is that the first one has search method while in the second example search method is commented out. If you open console, you will see that search method somehow causes onChange to happen (twice!) when sortable tree is loaded. You don't need to type anything into search input. By my opinion this is wrong, because user doesn't change anything on sortable tree, however onChange happens.