old_contents: module.exports = function(config) {
      config.set({
          basePath: '',
          frameworks: [
              'mocha',
              'browserify',
              'detectBrowsers'
          ],
  
          files: [
              '../test_tmp/browser/Adapters.test.js',
              '../test_tmp/browser/RxBroadcastChannel.test.js',
              '../test_tmp/browser/Insert.test.js',
              '../test_tmp/browser/Observe.test.js',
              '../test_tmp/browser/CrossInstance.test.js',
              '../test_tmp/browser/LeaderElection.test.js'
          ],
          port: 9876,
          colors: true,
          autoWatch: false,
  
          /**
           * see
           * @link https://github.com/litixsoft/karma-detect-browsers
           */
          detectBrowsers: {
              enabled: true,
              usePhantomJS: false,
              postDetection: function(availableBrowser) {
                  console.log('aaaaaaaa');
                  console.dir(availableBrowser);
  
  //                return ['Firefox']; // comment in to test specific browser
  
                  return availableBrowser
                      .filter(b => !['PhantomJS', 'FirefoxAurora', 'FirefoxNightly'].includes(b));
              }
          },
  
          // Karma plugins loaded
          plugins: [
              'karma-mocha',
              'karma-browserify',
              'karma-chrome-launcher',
              'karma-edge-launcher',
              'karma-firefox-launcher',
              'karma-ie-launcher',
              'karma-opera-launcher',
              'karma-detect-browsers'
          ],
  
          // Source files that you wanna generate coverage for.
          // Do not include tests or libraries (these files will be instrumented by Istanbul)
          preprocessors: {
              '../test_tmp/browser/*.test.js': ['browserify']
          },
  
          client: {
              mocha: {
                  bail: true
              }
          },
  
  
          singleRun: true
      });
  };
  
new_contents: module.exports = function(config) {
      config.set({
          basePath: '',
          frameworks: [
              'mocha',
              'browserify',
              'detectBrowsers'
          ],
  
          files: [
              '../test_tmp/browser/Adapters.test.js',
              '../test_tmp/browser/RxBroadcastChannel.test.js',
              '../test_tmp/browser/Insert.test.js',
              '../test_tmp/browser/Observe.test.js',
              '../test_tmp/browser/CrossInstance.test.js',
              '../test_tmp/browser/LeaderElection.test.js'
          ],
          port: 9876,
          colors: true,
          autoWatch: false,
  
          /**
           * see
           * @link https://github.com/litixsoft/karma-detect-browsers
           */
          detectBrowsers: {
              enabled: true,
              usePhantomJS: false,
              postDetection: function(availableBrowser) {
  
  //                return ['Firefox']; // comment in to test specific browser
  
                  return availableBrowser
                      .filter(b => !['PhantomJS', 'FirefoxAurora', 'FirefoxNightly'].includes(b));
              }
          },
  
          // Karma plugins loaded
          plugins: [
              'karma-mocha',
              'karma-browserify',
              'karma-chrome-launcher',
              'karma-edge-launcher',
              'karma-firefox-launcher',
              'karma-ie-launcher',
              'karma-opera-launcher',
              'karma-detect-browsers'
          ],
  
          // Source files that you wanna generate coverage for.
          // Do not include tests or libraries (these files will be instrumented by Istanbul)
          preprocessors: {
              '../test_tmp/browser/*.test.js': ['browserify']
          },
  
          client: {
              mocha: {
                  bail: true
              }
          },
  
  
          singleRun: true
      });
  };
  
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