While the other annotations are drawn on top of the content, the highlight annotation is behind the text it highlights. In other words, it has to be inserted at a specific place in the ContentElementsUILayer. The pdf seems to mark the precise place where the highlight should be placed with the BDC, MCID and EMC operators in the content. At the moment, the read-only rendering of the highlight annotation has been implemented with an instance of the AnnotationUILayer called "HighlightUILayer" which is placed behind the ContentElementsUILayer. With this implementation, depending on the contents of the pdf, the highlight annotation might be visible or it might not be. 

To reproduce:
- Drop a RadPdfViewer on a blank form at design time. 

Some documents reqire this assembly as well. 

This exception seems to be related to AES algorithm PaddingMode property. 

Add a navigation pane to view attachments under a pdf. it is possible to have various attachments under a pdf file, such has another pdf. For example, when converting an email with attachments, the resulting pdf has attachments. 

RadPdfViewer has no possibility to view those right now. Could be an event and let the calling program manage this.

For our needs, I would like an event, because our attached files are also pdfs, so I could open them in a new tab

Currently, Tab selects the next control.

Attached is sample PDF document. 

This is not a valid PDF scenario as having appearance state requires having multi-state appearances. However, we should handle this invalid document scenario on our side so that the app does not crash with NullReferenceException.

Overprinting is option in the GraphicState that allows combining colors when drawing one object above another object.  It is briefly described on page 284 and page 565 in PdfReference 1.7. However, the result of overprinting is device dependent and there are no strict instructions how the result should look like. This feature also includes support for the different blending modes.

To reproduce: please run the attached sample project. If you reload the document, the horizontal scrollbar is not shown.

Workaround:
        public RadForm1()
        {
            InitializeComponent();

            this.radPdfViewer1.FitToWidth = false;
            this.radPdfViewer1.ViewerMode = Telerik.WinControls.UI.FixedDocumentViewerMode.None;
            this.radPdfViewer1.EnableThumbnails = false; 
            this.radPdfViewer1.DocumentLoaded += radPdfViewer1_DocumentLoaded;
            this.radPdfViewer1.LoadDocument(@"..\..\Go Air - Himanshe Ajeet Dubey - 17-01-2018 - Ranchi to Mumbai.pdf");
            Application.DoEvents();
        }

        private void radPdfViewer1_DocumentLoaded(object sender, EventArgs e)
        {
            Application.DoEvents();
            this.radPdfViewer1.FitToWidth = true;
        }

Load a file in RadPdfViewer, select some of the text, right click and select Copy. A sample pdf file is attached.

This dialog appears when one is clicking the signature field in the document. 

Please refer to the attached gif file and sample project. When you hide the overflow button with the first pixel, although it is indicated as Visible, it is actually not shown.

Workaround: Timer timer = new Timer();

private void commandBarStrip_ItemOverflowed(object sender, EventArgs e)
{
    timer.Interval = 100;
    timer.Tick += timer_Tick;
    timer.Start();

}

private void timer_Tick(object sender, EventArgs e)
{
    timer.Tick -= timer_Tick;
    var commandBarStrip = this.radPdfViewerNavigator1.CommandBarElement.Rows[0].Strips[0];
    commandBarStrip.OverflowButton.Visibility = ElementVisibility.Visible;
    timer.Stop();
}

 Currently, the first document is loaded. 

Workaround:
Wait for the document to load before loading the new document. 

The events should provide information as to when a page is about to be rendered and when it is displayed in the control.