Tested in Chrome v.24

Consider the following layouts

ViewPort (Border Layout) -> TabPanel(no defined Layout) -> TabPanel(VBox Layout)

If I place a GridPanel in the last TabPanel the rendering fails, while it works for a simple panel.

I've made a JSFiddle with the latest 4.2 RC Libraries which will show this behavior, just click on the failing tab . (The debug version prints Layout run failed to the console)

Do I miss something or is this a Bug?