Setting this value will override the default "dark" cursor color of black on non-touch devices. The reverse color is used when over an entry field and it is determined that the background of the entry field is a very light color.
This setting uses your Web Browser's Color editor - if you use IE11 instead of an HTML5 Browser like Edge or Chrome, an in-page editor is used.
See the Tile Background Color topic for an example using the Edge Editor.
In a Profile, this value can be inherited from a linked, parent profile. The Track Marks () will indicate if the value is default, from the parent Profile or unique to this profile.