I've seen this failing intermittantly a few times..
https://integration.wikimedia.org/ci/job/wmf-quibble-selenium-php72-docker/114590/console
[0-3] RUNNING in chrome - /repo/tests/selenium/specs/readmode.references.js [0-3] 2021-09-23T23:22:39.114Z ERROR @wdio/runner: Error: connect ECONNREFUSED 127.0.0.1:35455 at TCPConnectWrap.afterConnect [as oncomplete] (net.js:1107:14) [0-3] FAILED in chrome - /repo/tests/selenium/specs/readmode.references.js
npm ERR! code ELIFECYCLE npm ERR! errno 1 npm ERR! Wikibase@0.1.0 selenium-test: `npm-run-all --continue-on-error selenium-test:*` npm ERR! Exit status 1 npm ERR! npm ERR! Failed at the Wikibase@0.1.0 selenium-test script. npm ERR! This is probably not a problem with npm. There is likely additional logging output above.