Blue Box Outline When Using Find Functionality, mk II

This topic was opened in June last year and marked as answered, but if a satisfactory answer was given (which I doubt, because the person who raised it asked why), it certainly didn't appear in the discussion.

Anyway, the story is this: there are rare occasions when a PDF generated from an MS Word document using the Save As PDF option (tried with both Word 2010 on Windows 7 and Word 2016 on Windows 10) has an issue. The issue is: (1) search for a word (2) reader goes to first occurrence of the word but there is a big blue box ("halo") around it (3) try going to next occurrence, the cursor moves forward two letters within the found word; next occurrence, next two letters, and so on (3) Advanced Search shows many more occurrences of the word than are actually in the document, hundreds more in fact, and all these appear to be 2-letter strings from the actual search word.

When I look at such a document either in a web browser (tried with both Chrome & Firefox), or in a 3rd party reader like NitroPDF, everything is fine. You only get the word you are searching for. So the problem seems to be in Acrobat Reader DC.

Anybody want to try this, download the following PDF off a website (Disclaimer: I am not the author of this PDF. The author did supply me with the Word version of the document to experiment with, which is how I know the above. When I generated a PDF from that using NitroPDF, it did not have the problem):

http://www.colensostudy.id.au/Newsletters/Year%202018/Hooker%20in%20the%20Bay%20of%20Islands.pdf

I did submit a Bug Report to Adobe but as is usual, no feedback so far.