The upgrade from 2.1 to 2.4 caused custom search box theme selections to go away. I had to go in and re-select the grey theme and re-select the search active icon. This is a m inor problem but you should be aware of this case.
Thanks,
Ken Z
This is a known thing, it is stated in the documentation and on the product description page, that upgrading the search requires to delete/recreate the search instances 🙂
I have implemented a better upgrading system to 2.4, so this shouldn’t happen after this version.