Currently, the position and size of the merged cell can be fetched via the numeric position and length properties of the MergedCellInfo class. This allows you to implement custom code that iterates the Columns collection of RadGridView and extractс the parent GridViewColumn(s).

Add a property that allows you to get the columns hosting the merged cell. The property should be able to get a single column (when the cells are merged vertically) and multiple columns when (when merged horizontally).

We are using telerik:RadGridView.RowDetailsTemplate in our GridView and we need the ability to expand or contract all rows at the press of a button.  As in the demo code under Hierarchy, we need to do this from our ViewModel.  Can the IsExpandedBinding be implemented for this use case in addition to when using hierarchical data?  

Currently, within the LoadItems() method the items are being iterated directly, thus a second query to the database is triggered.  A separate list for this operation should be created.

Currently, when you click F2 or double mouse click in order to start editing a cell (with a TextBox editor) its text gets selected. This happens because the SelectAll() method of the underlying TextBox is called. Add a property that allows to disable this behavior and to avoid selecting the text.

At this point you can get this effect by creating a custom column and overriding its PrepareCellForEdit() method as shown here: https://docs.telerik.com/devtools/wpf/knowledge-base/kb-gridview-prevent-f2-text-selection 

Currently, the Control Panel button is placed in the same row like the group panel. This means that if you hide the group panel, but keep the Control Panel button, then you will end up with a single button an a considerable empty area on top of the GridView. This is noticeable mostly when you also display also the search panel. 

Add a property that allows you to move the position of the Control Panel button from the group panel's Grid row to the search panel's row. This way you can make the GridView more compact by placing the button in the search panel's area.

Currently, the elements in the row details are measured with infinity size. This means that if you want to limit the content within the available space of the row, you will need to set the Width of the content manually. Add a mechanism that allows you to alter this behavior and measure the child content with the available space.

It is difficult to track whether the newly added items are pasted or not crated by insert.

Not all of the FilteringControl elements have automation IDs. This fact prevents the proper usage of some automation frameworks.

Currently the new item's properties are validated before editing their values, which is not intuitive, especially for Required, MinLength etc. The correct behavior would suggest that validation should be applied only to "confirmed" property values.

Currently all of the MoveCurrentTo methods rely on the internal logic of MoveCurrentToPositionCore and users cannot override it through inheritance.