At the moment the theme of the RadPdfViewerToolBar can be set only by setting the theme of the entire application. The individual setting (using telerik:StyleManager.Theme="Windows8") should also be supported.

Currently, RadPdfViewer uses default constant value for the font size in this scenario.

When ScaleMode is set to FitToPage scrolling the Mousewheel or pressing the Arrow Down button does not produce immediate scroll. The page is scrolled to the next page after several scroll events/button presses are introduced.

Workaround: Provide custom ScrollCommand implementation.

An invalid certificate is not imported correctly and causes exception on export. We should be able to handle this and skip the import without breaking the file. 

Currently the minimal zoom out value is 0.8% which impacts the performance while scrolling large documents.

Implement editor functionalities like add, edit or delete content.

When rendering PDF file with a TrueType font and Unicode platform Id (platformId: 0), glyphs are not obtained from CMAP table and are displayed with default rectangle placeholders.

The issue is reproducible only on Windows XP. On newer versions of windows, the images are rendered as expected.

WORKAROUND: You may inherit DctDecode class in order to implement custom decoder. For instance, you may try calling DecodeWithJpegDecoder method from the base class as mentioned in the note of this documentation article:

http://docs.telerik.com/devtools/wpf/controls/radpdfviewer/customization-and-extensibility/customize-pdf-rendering

A sample implementation of these custom decoder may be seen below:

public class CustomDctDecode : DctDecode
{
    public override byte[] Decode(PdfObject decodedObject, byte[] inputData, DecodeParameters parms)
    {
        return DecodeWithJpegDecoder(inputData);
    }
}

The image quality is poor when rendering large images.

PDFViewer crashes, when used on a tablet, Text selection is activated and text is selected in Touch mode.

When Find Next is used multiple times fast, and pages are still loaded asynchronously, sometimes NullReferenceException is thrown with the following call stack:

System.NullReferenceException: Object reference not set to an instance of an object.
   at Telerik.Windows.Documents.Fixed.Text.TextRecognizer.GetLastCharacter()
   at Telerik.Windows.Documents.Fixed.Text.TextRecognizer.IsLineBreak(Glyph glyph)
   at Telerik.Windows.Documents.Fixed.Text.TextRecognizer.ProcessGlyph(Glyph glyph)
   at Telerik.Windows.Documents.Fixed.Text.TextRecognizer.CreateTextPage(RadFixedPageInternal page)
   at Telerik.Windows.Documents.Fixed.Text.TextDocument.GetTextPage(Int32 index)
   at Telerik.Windows.Documents.Fixed.Search.KMPTextSearch.FindNext(TextDocument document, TextPosition startPosition, String searchText, Boolean matchCase, Boolean wholeWordsOnly)
   at Telerik.Windows.Documents.Fixed.Search.TextSearch.Find(String text, TextSearchOptions options)

...

A similar scenario is not defined in the PDF specification but the widgets can be rendered as read-only fields despite the fields associated with them are missing.

When the Textbox` text alignment is set to top (multiline) left when entering in edit mode the alignment is changing to center-left (check the attached record.gif).

It is actually checked and only the appearance is wrong. When the file is saved the checkboxes states are as expected.

This behavior is observed with PdfImportSettings.ReadOnDemand setting only.

When the color of the image is using the CMYK color model, DctDecode filter is applied, and there is no ColorTransform set the colors of the image are inverted.

The selection position is wrong when each character is drawn with PDF operators 

Invalid character rendering with specific glyphs. For example, the two dots of the umlaut characters are not centered. 

While scrolling a document containing many Link annotations there is a decrease in the performance.

When importing a document containing a single associated widget annotation merged into the field dictionary the field is skipped on import and an exception is thrown.

According to the PDF Specification: Field Dictionaries: Kids:

An array of indirect references to the immediate children of this field.
In a non-terminal field, the Kids array is required to refer to field dictionaries that are immediate descendants of this field. In a terminal field, the Kids array ordinarily must refer to one or more separate widget annotations that are associated with this field. However, if there is only one associated widget annotation, and its contents have been merged into the field dictionary, Kids must be omitted.

There are missing characters when importing documents containing Standard fonts with a Differences array defined in the Encoding, which contains characters that do not fit in the first 255 glyph definitions in the font. Most of these characters are the ones with an accent such as "ccaron" (č).