An element the document can't have, such as <video> or <iframe>, which is left out
An image whose data isn't in the HTML or the images option, which is left out
An image in a format Word can't show, such as WebP, or data that isn't an image, which is left out
A link to a javascript: address, or another that could run code, whose text is kept without the link
Math that can't be read, whose text is kept
Content in more than a thousand elements in each other, whose text is kept without its formatting
A table, list or other block in HTML given to htmlToRuns, whose content is kept in the paragraph
A table in a note, whose cells' paragraphs are kept in the footnote or endnote without it
What kind of thing a warning is about