We found a bug related TabControl SelectedIndex.
Background info: as the CSHTML5 visual designer is a kind of one way "what-you-see-is-what you get":
it MEANS what you write in XAML code you will get the UI representation of it as a result,
but NO INTERACTIVITY: you can not click on any UI element and get selection&modify any property.
So, when you work with multi-tab UI (a TabControl with multiple TabItems) you have only 3 ways to see something:
1./ put the <TabControl SelectedIndex="3"> to point the index of actual TabItem (what you would like to see during design),
2./ put the actual/working Tabitem to the first place by manual copying,
3./ do a trick: open a XAML file "Add as a link" to another instance of VisualStudio (and put it in the WPF project).
When we use the first solution (1./) -to change the <TabControl SelectedIndex="X">- we got exception BUT ONLY IN BROWSER:
JSIL.Core.Types.js?20167221535:1 Uncaught RangeError: Maximum call stack size exceeded.
-A) if you leave <TabControl SelectedIndex="3"> in you XAML code, you will get exception in the browser runtime,
-B) for you kind information: if you call mainTabControl.SelectedIndex = 3; from code-behind: no problem, everything is perfect in both Simulator & Browser.
Waiting for your kind reply,