According to the PDF specification:
A clipping path operator (W or W*) may appear after the last path construction operator and before the path-painting operator that terminates a path object.

Invalid:

W                          % clipping path operator
0 0 m                     % start of the path construction
596 0 l
596 842 l
0 842 l
h                            % end of the path construction
n                            % path-painting operator

0 0 m
596 0 l
596 842 l
0 842 l
h
W
n

Currently (in the invalid cases), the path construction is skipped on import.

When using the Telerik.Documents.ImageUtils.JpegImageConverter default implementation in Blazor WebAssembly application the Magick.NET library doesn't load all of its assemblies.

Workaround:
Create a custom implementation of the JpegImageConverterBase class: Create Custom JpegImageConverter in .Net Standard.

When importing a document containing an invalid PDF object dictionary key an exception is thrown.

When importing a not embedded TrueType Font defined as Type 1 subtype Font an InvalidCastException is thrown.

In PDF document:

<< /BaseFont /Arial /Encoding 21 0 R /Name /F13 /Subtype /Type1 /Type /Font >>

In Adobe Reader:

Wrong encoding is used when the PDF file contains font with custom encoding

Workaround:

foreach (var widget in field.Widgets)
{
    widget.TextProperties.Font = FontsRepository.Helvetica;
}