ArgumentException when there are bookmarks that point to the same location: System.ArgumentException: 'An item with the same key has already been added.

Text is not displayed when using embedded subset of the ToyotaTypeLight font.

The read-only flag is not respected when importing a document

The images are loaded asynchronously and when scrolling too fast, the loader might fail to load an image if it is bigger.

When using SaveAsCommandDescriptor of RadPdfViewer and trying to replace a pdf file that is currently open in adobe reader causes the following exception:

 

System.IO.IOException: The process can not access file "C:\Temp\test.pdf" because it used by another process.
   at System.IO.__Error.WinIOError(Int32 errorCode, String maybeFullPath)
   at System.IO.FileStream.Init(String path, FileMode mode, FileAccess access, Int32 rights, Boolean useRights, FileShare share, Int32 bufferSize, FileOptions options, SECURITY_ATTRIBUTES secAttrs, String msgPath, Boolean bFromProxy, Boolean useLongPath, Boolean checkHost)
   at System.IO.FileStream..ctor(String path, FileMode mode, FileAccess access)
   at Microsoft.Win32.SaveFileDialog.OpenFile()
   at Telerik.Windows.Documents.Commands.SaveAsPdfDocumentCommand.Execute(Object parameter)
   at MS.Internal.Commands.CommandHelpers.CriticalExecuteCommandSource(ICommandSource commandSource, Boolean userInitiated)
   at System.Windows.Controls.Primitives.ButtonBase.OnClick()
   at System.Windows.Controls.Button.OnClick()
   at Telerik.Windows.Controls.RadButton.OnClick()
   at System.Windows.Controls.Primitives.ButtonBase.OnMouseLeftButtonUp(MouseButtonEventArgs e)
   [...]

When changing the device culture to RTL (e.g. Hebrew but not only) in a project targeting .NET 5 (or later), some documents are rendered incorrectly.

OverflowException is thrown while importing document using Helvetica font with custom encoding.

As a result, the glyphs are not measured and positioned properly. The issue applies to the TrueType and Type1 fonts.

When displaying PDF-Files using PDFViewer, ContentElementsCanvas .RenderAsync uses reflection (DispatcherObjectUtils.ApplyDispatcher) to render Visuals on multiple threads.
However this leads to a memory leak since the dispatchers cant be GC'ed, see screenshot below.




The Screenshot is from the actual application we expirienced this issue with, the attached reproduction example is a boiled down version of what your code does.
If you wanna reproduce this on your own, create an application that uses PdfViewer that switches between many pdf files. The ammount of Dispatchers will grow steadily, probably to a total of the number of threads used by Task.Factory.

Images hosted inside multiple Form XObjects are not rendered.

Some documents cannot be printed with the PdfViewer. In this case no exception is thrown and the result file is 0 bytes. 

When opening a document with a CFF Type1 font an exception is thrown: NullReferenceException: 'Object reference not set to an instance of an object.'

XObejcts with indirect reference to an image are not rendered.

When the font is not embedded in the document, PdfViewer tries to read it from the OS. However, the Calibri-Font is not properly parsed and a NullReferenceException is thrown internally for its encoding. 

The image inside an XObejct is not shown in the correct position. 

A password is asked although Adobe opens the document without one when the document is encrypted with "Encryption of data using the RC4 or AES algorithms with a file encryption key length of 40 bits." - Version 1 (V 1) Revision 2 (R 2).

Similar cases (V1 R3 and V2 R3) are handled in the following item: PdfViewer: A password is asked although Adobe opens the document without one.

When the Interactive Form Fields are in read-only mode, the user should not be able to change the value of the field. The associated Form Field widgets should not interact with the user, e.g. they should not respond to mouse clicks or change their appearance in response to mouse motions.

 Exception when rendering a file with a lot of RenderTargetBitmap objects (Com Exception: MILERR_WIN32ERROR). It seems that we are creating this for tilling patters which are not reused and we ca reconsider our appraoch.  

The text elements in a document are positioned wrongly and are slightly offset from their expected positions.

The "scn" value is not interpreted correctly which causes graphics to be drawn differently from Adobe.