I am working on a WordPress plugin. For part of it I am adding a Metabox onto the Post Edit screen in the admin section. However things stop working if I add a WP_List_Table. That is because by default the list table adds a _wpnonce field, even though there is already one there for the Edit page.
This of course messes things up and prevents you from saving or updating. Not awesome. The field is output in the display_tablenav() function in the base list_table class. It looks like there has been a fix submitted, lets hope it gets into an upcoming version.
Until then, you can simply override the display_tablenav() function with a blank function or one that provides similar functionality.