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.

This is reproducible when the matched result resides on different page.

Workaround: You may subscribe to the RadFixedDocument.CaretPosition.PositionChanged event and implement the scroll logic. Subscribe to PdfViewer's DocumentChanged event first if the document is not loaded.
        private void CaretPosition_PositionChanged(object sender, EventArgs e)
        {
            Telerik.Windows.Documents.Fixed.Model.RadFixedPage currentPage = this.pdfViewer.Document.CaretPosition.Page;
            int pageIndex = this.pdfViewer.Document.Pages.IndexOf(currentPage);
            this.pdfViewer.GoToPage(pageIndex + 1);
        }

Currently, we use System.Windows.Controls.TextBox for editing both TextBox and CombTextBox field types. We should implement CombTextBox editor which would allow having spaces between characters during the editing process.

RadPdfViewer's AcroForm property ViewersShouldRecalculateWidgetAppearances should be respected when being set to true. In this case, RadPdfViewer should recalculate all widget appearances and this would resolve the issue with empty form field widgets after opening such PDF document.

This would allow switching the focus between form field controls by using the Tab key.

This action is usually linked to a Button field and with it, the user of the application may revert all field values to their defaults. 

At this point, the Print() method allowing the customers to silently print a document uses the PrintableAreaWidth and PrintableAreaHeight properties of the print dialog, which are read-only and cannot be changed through the API. Consider changing them with PrintTicket.PageMediaSize.

We should also consider the scenario when the client needs to print a smaller PDF page on a bigger page size. For instance, A5 page to be printed on an A4 sheet without scaling the content.

An ArgumentException is thrown internally as the font name is null. However, the name is defined in the base font and can be obtained from it.

Fix available in LIB Version 2018.1.402.

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

This is reproducible when the field VariableTextProperties has zero value for font size. 

Fix available in LIB Version 2018.1.402.

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

This happens only in scenarios when the widget has On state appearance defined and Off state appearance missing. If both appearances are missing then RadPdfViewer recalculates the appearances and the checkbox is successfully selected and deselected.

The file contains the following:
68.637 604.561 455.981 -107.996 re
72.237 604.561 l
S
Instead of the more usual
68.637 604.561 455.981 -107.996 re
S
72.237 604.561 l
S
Both are valid but the first seems to create a problem.

Fix available in LIB Version 2018.1.319.

The exception is thrown when the RadioButtonField options array contains nested arrays instead of string values.

Fix available in LIB Version 2018.1.312.

This happens only in specific scenarios as most of the documents with annotations are visualized correctly.

Images decoded with CCITTFaxDecode filter affect the performance when showing the document.

Most PDF viewers have option (enabled by default) which allows fields to be highlighted with colors predefined in the settings. Required fields are highlighted using different color.

For example: In Adobe Acrobat Reader DC this is enabled in "Edit" -> "Preferences" -> "Forms" -> "Highlight Color" -> "Show border hover color for fields". 

Expose a button in the UI that can be used instead of Ctrl+F.

Such a button can be currently added by customizing the default toolbar. For more information, check the documentation that describes how to achieve that: https://docs.telerik.com/devtools/wpf/controls/radpdfviewer/default-ui#customizing-the-default-ui

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.

When a PDF is printed all images are omitted.

Available in R1 2018 SP1 version.