Try launching puppeteer instead of nightmare

src/karma.conf.js

@@ -1,11 +1,14 @@
 // Karma configuration file, see link for more information
 // https://karma-runner.github.io/1.0/config/configuration-file.html
 
+process.env.CHROME_BIN = require('puppeteer').executablePath();
+
 module.exports = function (config) {
   config.set({
     basePath: '',
     frameworks: ['jasmine', '@angular-devkit/build-angular'],
     plugins: [
+      require('karma-chrome-launcher'),
       require('karma-jasmine'),
       require('karma-nightmare'),
       require('karma-jasmine-html-reporter'),
@@ -25,7 +28,7 @@ module.exports = function (config) {
     colors: true,
     logLevel: config.LOG_INFO,
     autoWatch: true,
-    browsers: ['Nightmare'],
+    browsers: ['ChromeHeadless'],
     singleRun: false
   });
 };