Error running Protractor : "Error while running testForAngular: Unable to communicate to node" #40

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$ tsc -p e2e/tsconfig.e2e.json && protractor e2e/build/protractor.config.js
[06:26:44] W/driverProviders - Using driver provider hosted, but also found extra driver provider parameter(s): browserstackUser, browserstackKey
[06:26:44] I/launcher - Running 1 instances of WebDriver
[06:26:44] I/hosted - Using the selenium server at http://hub-cloud.browserstack.com/wd/hub
[06:27:00] W/runner - Ignoring unknown extra flags: target. This will be an error in future versions, please use --disableChecks flag to disable the  Protractor CLI flag checks.
...
Error: Error while running testForAngular: Unable to communicate to node
    at executeAsyncScript_.then (/home/workspace/project/node_modules/protractor/lib/browser.ts:945:27)
    at ManagedPromise.invokeCallback_ (/home/workspace/project/node_modules/selenium-webdriver/lib/promise.js:1366:14)
    at TaskQueue.execute_ (/home/workspace/project/node_modules/selenium-webdriver/lib/promise.js:2970:14)
    at TaskQueue.executeNext_ (/home/workspace/project/node_modules/selenium-webdriver/lib/promise.js:2953:27)
    at asyncRun (/home/workspace/project/node_modules/selenium-webdriver/lib/promise.js:2813:27)
    at /home/workspace/project/node_modules/selenium-webdriver/lib/promise.js:676:7
    at process._tickCallback (internal/process/next_tick.js:109:7)
[ERROR] Error: Error: Error while running testForAngular: Unable to communicate to node
    at /home/workspace/project/e2e/build/specs/home.spec.js:17:19
    at process._tickCallback (internal/process/next_tick.js:109:7)
[05:43:16] E/launcher - Process exited with error code 1