Created attachment 19096 [details]
With a master detail page if you resize the window of the app the menu disappears.
Attached you can find a repro project
1. Set ResizeWinIssue.Windows as startup project
2. Run the app
3. Select "Page 2" menu
4. Try to expand the size of the window
5. The menu disappears.
IsPresented is being set to false in OnItemSelected. Not setting this value to false will stop that menu from disappearing when resizing the window. I believe there are conflicting statements in the docs. The issue you are facing with this reproduction is not that the menu is disappearing, but that it is not disappearing when the value is set, which is a separate issue in itself.
Ok I see now..
IsPresented is set to false in our app to close the slide menu for iOS and Android phone.
I can check the OS and Idiom to fix this.
Thanks for your support
But I would say you should implement the same behaviour in WinRt desktop that you have for iOS and Android tablet. IsPresented set to false has no effect to the menu.
Should be fixed in 2.3.5-pre1