1) Open WPF Demos and maximize it
2) Open "Alert, Prompt and Confirm" sample
3) Click "Confirm"
4) Minimize all windows (for example, by using Win+D)
5) Switch to WPF Demos again
6) Now you can't do anithing with the window, even close it. You can use task manager to close it.

It happens when IsRestrictedWhenMaximized set to true.

Available in LIB version 2015.3.1012, it will be also available in the 2015 Q3 SP.

If RadWindow has its Width set to a value greater that 50% of the screen and that window is snapped to the left or right, performing minimize and then restore leads to incorrect normal size .

Available in LIB version 2015.3.1123, it will be also available in the 2016 Q1 release.

This can be observed only when AllowTransparance is set to false.

When EventBinding is used in XAML to bind commands to events of Window or RadRibbonWindow (as it inherits Window), InvalidOperationException is thrown in design-time.

Workarounds: 
1. Attach an event handler directly to the events of the Window (RadRibbonWindow)
2. (more MVVM-friendly) use Behavior to attach the appropriate event handler.

As an example Windows 10 OS Window gets different Opacity for its Title and Buttons when Inactive (open two Window-s and make them appear one behind the other -- the one in the background of the active window is inactive). Our Office2016 and Office2016 Touch themes are inspired by Windows 10 OS as we officially stated so we might mind adding this visual appearance on our side for RadWindow.

 

The Window gets clipped on the right side when using a dual monitor setup when the taskbar is on the left/right side of the screen and the app must be running maximized on the secondary screen.

After fixing this BUG (Release LIB 2019.3.930), an additional issue is found.

A window is in Maximized or Normal state, click on the application icon in the taskbar to minimize it and click again to restore the window. It gets clipped to ~160*26 pixels. After clicking on this header, it gets restored to Maximized or Normal state depending on the initial state.

I have a two-monitor setup with identical resolutions (FullHD on both monitors) and Scale is 100% on both monitors.

This exception is thrown when the CanExecute method of the Command bound to a response button returns false when the response button key is pressed. 

Hi,

   There is a bug in version 2019.3.1023.45 RadWindow when I minimum and restore window from task bar

This behavior can be observed when the ResizeMode property of RadWindow is set to CanResizeWithGrip. 

ArgumentOutOfRangeException can be thrown when showing/closing windows in a multi-threaded application. Here's a possible stack trace:

System.ArgumentOutOfRangeException: Index was out of range. Must be non-negative and less than the size of the collection.
Parameter name: index
   at System.ThrowHelper.ThrowArgumentOutOfRangeException(ExceptionArgument argument, ExceptionResource resource)
   at System.ThrowHelper.ThrowArgumentOutOfRangeException()
   at System.Collections.Generic.List`1.RemoveAt(Int32 index)
   at System.Collections.Generic.List`1.Remove(T item)
   at Telerik.Windows.Controls.RadWindowManager.RemoveWindow(WindowBase window)
   at Telerik.Windows.Controls.WindowBase.OnClosed()
   at Telerik.Windows.Controls.RadWindow.OnClosed()
   at Telerik.Windows.Controls.WindowBase.CloseHostImidiately()
   at Telerik.Windows.Controls.WindowBase.TryClose(Boolean shouldCloseHost)
   at Telerik.Windows.Controls.WindowBase.Telerik.Windows.Controls.InternalWindow.IWindowDragAware.TryClose(Boolean shouldCloseHost)
   at Telerik.Windows.Controls.InternalWindow.WindowWithNoChromeWindowHost.OnWindowClosing(Object sender, CancelEventArgs e)
   at System.Windows.Window.OnClosing(CancelEventArgs e)
   at System.Windows.Window.WmClose()
   at System.Windows.Window.WindowFilterMessage(IntPtr hwnd, Int32 msg, IntPtr wParam, IntPtr lParam, Boolean& handled)
   at System.Windows.Interop.HwndSource.PublicHooksFilterMessage(IntPtr hwnd, Int32 msg, IntPtr wParam, IntPtr lParam, Boolean& handled)
   at MS.Win32.HwndWrapper.WndProc(IntPtr hwnd, Int32 msg, IntPtr wParam, IntPtr lParam, Boolean& handled)
   at MS.Win32.HwndSubclass.DispatcherCallbackOperation(Object o)
   at System.Windows.Threading.ExceptionWrapper.InternalRealCall(Delegate callback, Object args, Int32 numArgs)
   at System.Windows.Threading.ExceptionWrapper.TryCatchWhen(Object source, Delegate callback, Object args, Int32 numArgs, Delegate catchHandler)
   at System.Windows.Threading.Dispatcher.WrappedInvoke(Delegate callback, Object args, Int32 numArgs, Delegate catchHandler)
   at System.Windows.Threading.Dispatcher.LegacyInvokeImpl(DispatcherPriority priority, TimeSpan timeout, Delegate method, Object args, Int32 numArgs)
   at System.Windows.Threading.Dispatcher.Invoke(DispatcherPriority priority, Delegate method, Object arg)
   at MS.Win32.HwndSubclass.SubclassWndProc(IntPtr hwnd, Int32 msg, IntPtr wParam, IntPtr lParam)

If you open the window on a specific resolution, maximize it and then change the resolution to a bigger one, the window size is not updated. The window stays in the original resolution of the screen.

To work this around subscribe to the SystemEvents.DisplaySettingsChanged event and reset the WindowState of RadWindow.