« XUL Reference
toolboxid
Type: string
The ID of the toolbox this toolbar is a member of. This will either be the toolbox's parent (if it's in a toolbox), or, if the toolbar is an external toolbar (that is, one not contained in a toolbox), the ID of the toolbox it should be considered to be part of. This makes it possible to have toolbars that are not contained within toolboxes, such as the add-on bar.