What's said here is spot on. The best practices on SPL2 and AppInspect warn against doing this, yet it's the only way to get things working.
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A new version 2.3.1 will be pushed soon to fix this error. A workaround is to install the app on each of the indexers - though in your case it looks like you want to avoid utilizing the indexers - in which case you will want to continue to use the accepted answer even after the upgrade.
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