# Kupu Toolbar Configuration

Global button visibility
You may enter an expression to control the visibility of all buttons together. It should return a list of visible button ids, or None to leave all buttons visible. The visibility rules below are then applied to further filter out individual buttons. You might use this to restrict a particular class of users to a subset of kupu functions.
Button visibility
Control the global visibility of toolbar buttons from this screen. If no expression is entered, only checked buttons are visible. Enter an expression for finer control of visibility. Individual fields may also whitelist or blacklist buttons: see the field schema.
Values available in expressions includes 'field' as well as the usual names
e.g. to restrict the drawer buttons to users with the appropriate permissions give imagelibdrawer-button and linklibdrawer-button the expression:
`python:member and member.has_permission('Kupu: Query libraries',portal)`

| ID | Title | Visible | Expression