I want to get ItemsSource by retrieving a list from a dictionary, so I need 2 parameters, but I can't use MultiBinding to do this!

When dealing with Date column filters show available options (similar to text filters) and support grouping based on Year, Month. This is a very handy feature of Excel.

When TabStopMode is set to "Skip" on all columns and you press Tab, RadGridView scrolls a little.

Workaround: define a custom KeyboardCommandProvider and clear the pending commands.

It's so strange that Telerik's components don't support such basic mechanics of WPF...

The same works fine with the old Nested mode.

Enhance aggregate functions (like Sum) in footers so they support expression columns in RadGridView. 

See the attached project. It works for DataColumn, but raises an exception that no suitable generic Sum method could be found when I set the Sum footer for an expression column.