Hi, I have problems when updating my tabbed panels :'( After modifying the data on one panel I update several other panels, that are not necessarily connected together. Using only #update e.g. (browser paneNamed: #example) update. The data is correctly updated, but not the presentations. Based on the example #updateableBrowser I am showing the errors. 1) #when in the second list does not react. * If you start with an empty collection, the list does not appear, then if you add an element the list does not appear neither. * if you start with some elements, the list is there, but after removing all the elements the list does not disappear, and instead you have a SubscriptOutOfBounds error because of a tab index (this is my same scenario: tabbed panels) 2) #shouldValidate: what is the logic of this?. I tried to use it, but i got into problems on the selected item. I could only inspect the selected item of the panel using #shouldValidate. In the second panel -> selected item is nil or the value of the first panel. | browser collection | collection := GLMAnnouncingCollection new. collection add: 1. browser := GLMTabulator new. browser column: #automatic; column: #menu. browser act: [:b | b entity add: (b entity size + 1) ] entitled: 'Add an item in the collection'. browser act: [:b | b entity removeLast ] entitled: 'Remove last item from the collection'. browser act: [:b | b update ] entitled: 'Update complete browser'. browser transmit to: #automatic; andShow: [ :a | a title: 'Updated automatically'. a stackedArrangement. a list title: [:x | 'List: ', x size printString ]; shouldValidate: true; updateOn: GLMItemAdded from: #yourself; updateOn: GLMItemRemoved from: #yourself ]. browser transmit to: #menu; andShow: [ :a | a title: 'Updated via menu'. a list title: 'List'; when:[ :e| e size > 0 ]; act: [:p | p update ] entitled: 'Update'. a text title: 'Text'; act: [:p | p update] entitled: 'Update'. ]. browser openOn: collection Please some help. Best Regards, Veronica