When I create toolbar button in CKEditor 3.0 with following code I need to uncomment icon property to get button visible. Otherwise space is occupied but no label is shown. When I hover over it I get caption popping up.
        editor.ui.addButton('customButton', {
            label: 'Custom Action',
            //icon: this.path + 'images/anchor.gif',
            command: commandName
        });
Do you know how to create toolbar button without icon? Just a pure text.