First Footer of a section overrides the First Footer of another section after the merge. After merging 'Parent' document (with a different First Footer which is empty) with 'Child' document (with explicitly set First Footer), the First Footer of 'Child' overrides the First Footer of 'Parent' after PDF export.

Workaround 1: Disable 'Child' document's 'HasDifferentFirstPageHeaderFooter' and clear its First Footer's value:

Telerik.Windows.Documents.Flow.Model.Section section = child.Sections.First();
section.HasDifferentFirstPageHeaderFooter = false;
section.Footers.First.Blocks.Clear();

parent.Sections.First().Footers.Add(HeaderFooterType.First);

Similar to https://feedback.telerik.com/reporting/1356710-rendering-to-xlsx-should-not-add-bom-to-xml-files :

DOCX files exported with DocxFormatProvider contain a BOM in every exported XML file. Some programs fail to load those DOCX files.

Please remove the BOM, or add a toggle in DocxExportSettings.

If a TOC field uses TC fields only (with the \f switch) and there is a tab in the text of the TC field, after mail merge, the tab becomes really wide. If the file is opened in word and the field is updated, everything goes back to normal.

Expected:

Actual:

A possible workaround is to set the fields to be updated on opening of the document:

DocxFormatProvider provider = new DocxFormatProvider();
provider.ExportSettings.AutoUpdateFields= true;

When a span has nested strikethrough and underline tags applied to it only the inner tag is respected.

This HTML:

results in:

UnderlineStrikethrough

And this HTML:

results in:

UnderlineStrikethrough

As a possible workaround, you can add some text placeholder to the span that needs both "underline" and "strikethrough" and after import set the properties, and remove the placeholder text.

Sample HTML:

after import, execute this: