I have a complex web of interaction!
My main page has my ListManager on it which creates a BorderLayout with a Grid in north, and several ContentPanels added as tabs to the center.
A couple of those ContentPanels create ListManagers.
My ListManager puts the class "asp-listmanager" on its container, and when created, scans up the parentNode axis, and finds its containing ListManager. If it finds one, it sets monitorWindowResize to false in its own BorderLayout, and subscribes to the parent ListManager's "layout" event.
This works great, all my child ListManagers lay themselves out when I collapse the parent's north region.
Problem is, that in hidden tabs the width gets set to zero, so when I next visit that tab, I see blue.
tweaking the browser window to resize triggers the main ListManager's layout, which causes the ListManager in the blank tab to lay itself out, and it reappears.
This is a bug? Or is calling layout() on a BorderLayout on a hidden tab forbidden?