diff --git a/lib/browser.ts b/lib/browser.ts
index 4c9ae714b..54a40c3dd 100644
--- a/lib/browser.ts
+++ b/lib/browser.ts
@@ -758,7 +758,7 @@ export class ProtractorBrowser extends Webdriver {
             clientSideScripts.testForAngular, msg('test for angular'),
             Math.floor(timeout / 1000), this.ng12Hybrid)
         .then(
-            (angularTestResult: {ver: string, message: string}) => {
+            (angularTestResult: {ver: number, message: string}) => {
               let angularVersion = angularTestResult.ver;
               if (!angularVersion) {
                 let message = angularTestResult.message;
@@ -775,8 +775,8 @@ export class ProtractorBrowser extends Webdriver {
         .then(loadMocks, deferred.reject);
 
     let self = this;
-    function loadMocks(angularVersion: number) {
-      if (angularVersion === 1) {
+    function loadMocks(angularVersion: string) {
+      if (angularVersion == '1') {
         // At this point, Angular will pause for us until
         // angular.resumeBootstrap
         // is called.
diff --git a/lib/driverProviders/driverProvider.ts b/lib/driverProviders/driverProvider.ts
index fc67b5cd7..dd3346b7c 100644
--- a/lib/driverProviders/driverProvider.ts
+++ b/lib/driverProviders/driverProvider.ts
@@ -4,7 +4,9 @@
  *  it down, and setting up the driver correctly.
  */
 import * as q from 'q';
+
 import {Config} from '../config';
+
 let webdriver = require('selenium-webdriver');
 
 export class DriverProvider {
@@ -61,7 +63,7 @@ export class DriverProvider {
     if (driver.getSession() === undefined) {
       deferred.resolve();
     } else {
-      driver.getSession().then((session_: string) => {
+      driver.getSession().then((session_) => {
         if (session_) {
           driver.quit().then(function() {
             deferred.resolve();
diff --git a/lib/element.ts b/lib/element.ts
index d9fead9b5..6083eab09 100644
--- a/lib/element.ts
+++ b/lib/element.ts
@@ -178,32 +178,25 @@ export class ElementArrayFinder extends WebdriverWebElement {
               }
             });
       } else {
-        return this.getWebElements().then(
-            (parentWebElements: webdriver.WebElement[]) => {
-              // For each parent web element, find their children and construct
-              // a
-              // list of Promise<List<child_web_element>>
-              let childrenPromiseList = parentWebElements.map(
-                  (parentWebElement: webdriver.WebElement) => {
-                    return locator.findElementsOverride ?
-                        locator.findElementsOverride(
-                            ptor.driver, parentWebElement, ptor.rootEl) :
-                        parentWebElement.findElements(locator);
-                  });
+        return this.getWebElements().then((parentWebElements: WebElement[]) => {
+          // For each parent web element, find their children and construct
+          // a list of Promise<List<child_web_element>>
+          let childrenPromiseList = parentWebElements.map(
+              (parentWebElement: webdriver.WebElement) => {
+                return locator.findElementsOverride ?
+                    locator.findElementsOverride(
+                        ptor.driver, parentWebElement, ptor.rootEl) :
+                    parentWebElement.findElements(locator);
+              });
 
-              // Resolve the list of Promise<List<child_web_elements>> and merge
-              // into
-              // a single list
-              return wdpromise.all(childrenPromiseList)
-                  .then((resolved: webdriver.WebElement[]) => {
-                    return resolved.reduce(
-                        (childrenList: webdriver.WebElement[],
-                         resolvedE: webdriver.WebElement) => {
-                          return childrenList.concat(resolvedE);
-                        },
-                        []);
-                  });
-            });
+          // Resolve the list of Promise<List<child_web_elements>> and merge
+          // into a single list
+          return wdpromise.all(childrenPromiseList).then((resolved) => {
+            return resolved.reduce((childrenList, resolvedE) => {
+              return childrenList.concat(resolvedE);
+            }, []);
+          });
+        });
       }
     };
     return new ElementArrayFinder(this.browser_, getWebElements, locator);
@@ -501,7 +494,9 @@ export class ElementArrayFinder extends WebdriverWebElement {
    * @returns {!webdriver.promise.Promise} A promise which will resolve to
    *     an array of ElementFinders represented by the ElementArrayFinder.
    */
-  then(fn?: Function, errorFn?: Function): wdpromise.Promise<any[]> {
+  then(
+      fn?: (value: any) => {} | wdpromise.IThenable<{}>,
+      errorFn?: (error: any) => any): wdpromise.Promise<any[]> {
     if (this.actionResults_) {
       return this.actionResults_.then(fn, errorFn);
     } else {
@@ -726,7 +721,7 @@ export class ElementArrayFinder extends WebdriverWebElement {
 export class ElementFinder extends WebdriverWebElement {
   parentElementArrayFinder: ElementArrayFinder;
   elementArrayFinder_: ElementArrayFinder;
-  then: (fn: Function, errorFn: Function) => wdpromise.Promise<any> = null;
+  then: (fn: Function, errorFn?: Function) => wdpromise.Promise<any> = null;
 
   constructor(
       public browser_: ProtractorBrowser,
@@ -751,14 +746,16 @@ export class ElementFinder extends WebdriverWebElement {
        * of
        *     evaluating fn.
        */
-      this.then = (fn: Function, errorFn: Function) => {
-        return this.elementArrayFinder_.then((actionResults: any) => {
-          if (!fn) {
-            return actionResults[0];
-          }
-          return fn(actionResults[0]);
-        }, errorFn);
-      };
+      this.then =
+          (fn: (value: any) => {} | wdpromise.IThenable<{}>,
+           errorFn?: (error: any) => any) => {
+            return this.elementArrayFinder_.then((actionResults: any) => {
+              if (!fn) {
+                return actionResults[0];
+              }
+              return fn(actionResults[0]);
+            }, errorFn);
+          };
     }
 
     // This filter verifies that there is only 1 element returned by the
diff --git a/lib/expectedConditions.ts b/lib/expectedConditions.ts
index a44c6a390..c01d833ef 100644
--- a/lib/expectedConditions.ts
+++ b/lib/expectedConditions.ts
@@ -214,7 +214,8 @@ export class ProtractorExpectedConditions {
       Function {
     var hasText = () => {
       return elementFinder.getText().then((actualText: string): boolean => {
-        // MSEdge does not properly remove newlines, which causes false negatives
+        // MSEdge does not properly remove newlines, which causes false
+        // negatives
         return actualText.replace(/\r?\n|\r/g, '').indexOf(text) > -1;
       });
     };
diff --git a/lib/runner.ts b/lib/runner.ts
index 10da89d8b..a5c73a2a1 100644
--- a/lib/runner.ts
+++ b/lib/runner.ts
@@ -14,6 +14,7 @@ import * as helper from './util';
 
 declare var global: any;
 declare var process: any;
+declare var Object: any;
 
 var webdriver = require('selenium-webdriver');
 let logger = new Logger('runner');
@@ -258,7 +259,8 @@ export class Runner extends EventEmitter {
       // calls here are not guaranteed to complete before the tests resume.
       this.driverprovider_.quitDriver(browser_.driver);
       // Copy mock modules, but do not navigate to previous URL.
-      browser_ = browser_.forkNewDriverInstance(false, true);
+      let forkBrowser = browser_.forkNewDriverInstance(false, true);
+      browser_.driver = forkBrowser.driver;
       this.setupGlobals_(browser_);
     };