I'm using a custom SettingsPane based on the one you developped (Telerik\UI for WPF R2 2017\Themes.Implicit\WPF40\Windows7\Themes). This pane is used to customize all of the shapes (basic RadShapes and custom shapes) in a RadDiagram.
In this pane, there is a tab (it content is a UserControl) which allows the user to add values (from a RadGridView) to a serie in a RadChart (ScatterChart). The RadGridView allows the copy/paste functionnality to paste some values from Excel (for example).
However, I have a strange behavior about the focus: if I open the pane and the dedicated tab, I go to Excel to copy the data, click on the RadGridView before paste the data, then the main window and the pane don't take the focus. On the contrary, if I copy the data before opening the pane and the tab, there aren't any problems with the focus, the pasting is correctly done.
When the problem occurs, we can see that the main window header is light grey, to indicate that it doesn't have the focus.
Do you know something about this behavior? Do you have any solution?