Lovely as that thought is, there are failed builds for post 5.12.1- commits
Don’t be too mad at NPM, it’s trying it’s best! 
Finally had a change to start an ubuntu vm and try this. I don’t get an error after a clean clone in the commit you stated before. It might have been a temporary solution or a missisng npm install. If you are still experiencing it, let me know. I sadly can’t reproduce.
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I had the same problem, and did what jelster did and just installed the packages that were missing. These were removed from my project when I updated to the lastest (5.16) version from 5.9.
Installing the packages fixed the problems.
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Ohhh I didn’t consider that possibility! Maybe that’s what happened - the package got removed at some point after an upgrade
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