My NextGEN Gallery plugin as well as WordPress are both up to date.
I'm getting an error about the following deprecated call coming from NextGEN Gallery:
Incorrect Use of register_uninstall_hook()
Used in wp-content/plugins/nextgen-gallery/nggallery.php on line 79.
Only a static class method or function can be used in an uninstall hook.
This message was added in version 3.1.