RadPdfViewer does not read image resources defined in Form XObject elements.

Some of the lines that should be dashed are rendered as continuous lines.

The slow performance when creating thumbnail is only reproducible with specific documents.

Observed when loading a document: 

The issue occurs when RadPdfViewer is measured in infinite space, for example:
- Added to StackPanel.
- Added to RadWindow with Auto dimensions.

Workaround: Width and Height of RadPdfViewer can be set.

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.

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

While all the pages and components of the control are rendered on the image, the content is completely missing from it. The issue is a regression caused by the migration of the model and its async rendering introduced in R3 2020.

Workaround: Fallback to the old rendering engine:

• Changing the default behavior:

 this.pdfViewer.DefaultImportSettings.UseOldRendering = true;

• Setting the property to the format provider used to show the document:

PdfImportSettings settings = PdfImportSettings.ReadOnDemand;
settings.UseOldRendering = true;