passes firefox 39 but not chrome 40

package.json

@@ -109,7 +109,7 @@
         "eslint": "^8.36.0",
         "eslint-config-prettier": "9.0.0",
         "eslint-plugin-prettier": "3.4.1",
-        "fetch-mock": "^7.5.1",
+        "fetch-mock": "9.1.1",
         "gts": "^5.0.1",
         "jest": "^29.5.0",
         "jest-environment-jsdom": "^29.5.0",
@@ -139,7 +139,7 @@
         "webpack-cli": "^5.0.2"
     },
     "dependencies": {
-        "@babel/runtime": "^7.6.0",
+        "@babel/runtime": "^7.23.2",
         "core-js": "^3.33.0",
         "slugify": "^1.3.6"
     }

rollup.config.js

@@ -20,14 +20,6 @@ const defaultBabel = babel({
     babelHelpers: 'runtime',
 });
 
-const testBabel = babel({
-    ...babelSettings,
-    // extensions,
-    // include: ['src/**/*'],
-    babelHelpers: 'runtime',
-    plugins: ['@babel/plugin-transform-runtime'],
-});
-
 const babelMinify = babel({
     extensions,
     include: ['src/**/*'],
@@ -64,22 +56,6 @@ const builds = {
             json(),
         ],
     },
-    tests: {
-        input: 'test/cross-browser-testing/test-cross-browser.js',
-        output: {
-            ...defaultOutputOptions,
-            file: 'dist/CBT.js',
-            format: 'iife',
-            name: 'mParticle',
-        },
-        plugins: [
-            resolve(),
-            commonjs({
-                // include: 'node_modules/**',
-            }),
-            testBabel,
-        ],
-    },
     cjs: {
         input: 'src/mparticle-instance-manager.js',
         output: {

rollup.test.config.js

@@ -15,13 +15,14 @@ const builds = {
             file: 'test/test-bundle.js',
             format: 'iife',
             name: 'mParticleTests',
+            globals: 'browser_global',
             sourcemap: ENVIRONMENT !== 'prod',
         },
         plugins: [
             resolve(),
             commonjs({
                 include: 'node_modules/**',
-                namedExports: { chai: ['expect'] },
+                // namedExports: { chai: ['expect'] },
             }),
             babel({
                 extensions,