I don't make use of a self-signed server TLS/SSL certificate and I haven't tried to. Thanks to you, now I also need not try.
Assuming you also are making use of Node.js v8.12.0-x64, take note of the fact that in the meantime there is a new Node.js installer installing non-beta Node.js v10.13.0(-x64) Long Term Support (LTS) including the npm package manager, a command line client included as a recommended feature in Node.js installer that interacts with a remote registry. The installation got much more sophisticated since mid-October 2018 and at least visually makes a professional impression. However, as expected, it does not do everything it is promising.
With full details cf. Section Installing Node.js v10.13.0(-x64) presented on an intermittently with intermediate interruptions, as a general rule between 20:00 and 07:00 GMT/UTC o'clock, and temporarily operated web server.
After involving the updated Node.js run-time environment, the reference symptom overview, slightly extended based on @Mordax's post, hasn't changed significantly after all.
As a result, current reference working hypothesis is still valid. However, assuming no coding flaw in the NSS scripts themselves, I'm in the meantime slowly coming to conclusion that the NSS consistently initialized itself with the owner's WebID when installed and that the owner's WebID-OIDC protocol installation hardly is the culprit variable.
I'm hardly going to build Node.js from source in this reincarnation of myself.
The last resort would be trying to contact the authoring poets and asking them to at least buy a beer for each of us ♨ for—no offense meant—lavishing their poem on us and for (to an extent) wasting my youth on it.