Thanks, Glenn. Arnie's tip about editing site.conf solved my original problem. After that was settled, I took your advice to get a new version of node from their github page. Now I have node v23.11.0 and npm version 10.9.2, and the "npm ci" script completes successfully. It's a glorious spring day and I can go back to inventing vector calculus puzzles!
Installation
Problems render in some places but not others
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