In this feature, the existing text is overridden as the user types on it with the "Insert" key is pressed on the keyboard.

Workaround: Track the state of the Insert key and delete before inserting content using the KeyDown and CommandExecuting events:

private void MainDemoControl_KeyDown(object sender, System.Windows.Input.KeyEventArgs e)
{
    if (e.KeyboardDevice.IsKeyToggled(Key.Insert))
    {
        this.isInsertKeyPressed = true;
    }
    else
    {
        this.isInsertKeyPressed = false;    
    }
}
private void radRichTextBox_CommandExecuting(object sender, CommandExecutingEventArgs e)
{
    if (e.Command is InsertTextCommand && this.isInsertKeyPressed)
    {
        this.radRichTextBox.Delete(false);
    }
}

Using the microsoft word,In docx document,inserting a shape,and add the text context to the shape,then save.

when radrichtextbox  open the file,the program crashed.

When a whole paragraph is selected and the Set Numbering Value command is executed, the numbering value of the next paragraph is changed instead of the current one.

private void radRichTextBox_CommandExecuting(object sender, CommandExecutingEventArgs e)
{
    if (e.Command is ShowSetNumberingValueDialogCommand)
    {
        this.radRichTextBox.Document.CaretPosition.MoveToPosition(this.radRichTextBox.Document.Selection.Ranges.First.StartPosition);
    }
}

The issue is observed when the added table is preceded by a paragraph with a font size different from the default one. As the issue is caused by a broken mouse capture, the following workaround can be employed:

someRandomFrameworkElement.CaptureMouse();

someRandomFrameworkElement.ReleaseMouseCapture();