Punctuation marks and footnotes have disappeared

This is a re-post from what I posted in the Technical Support forum, as suggested by a moderator in that forum:

My document has long been in process. Therefore, it has seen an upgrade from Windows v1.9 to v3 Beta, and innumerable Beta updates. It has been a while since I have worked on this book. Now that I have begun again in earnest, my document in the latest Windows Beta ( has:

— replaced quotation marks, apostrophes, hyphens, bullet points, and other punctuation - with the exception of periods and commas - with black question mark icons
— made all the footnotes disappear

I have tried numerous font changes to no avail.

Has anyone experienced this issue, and is there a way restore the punctuation and footnotes?