I found out that WordPress has a filter that turns regular quotes into curly quotes for you, so text pasted from WP could be a problem.
In the old days, you could get rid of curly quotes by pasting stuff into Notepad and then pasting it back. I just tried it and it no longer works. I guess Notepad has gotten smarter.
After I made my post above, I thought of the irony of me saying, "who writes code in Word." I do. I wrote a ton of it for my book. I have a macro in Word (ctrl-q) that toggles the curly quotes feature.
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