Arguments display Specifies the connection to the X server. The mask is the bitwise inclusive OR of the valid keymask bits. A modifiers of AnyModifier is equivalent to issuing the ungrab request for all possible modifier combinations, including the combination of no modifiers. A button of AnyButton is equivalent to issuing the request for all possible buttons.
Some numeric value falls outside the range of values accepted by the request.
Unless a specific range is specified for an argument, the full range defined by the argument's type is accepted. Any argument defined as a set of alternatives can generate this error. BadWindow A value for a Window argument does not name a defined Window.