diff --git a/docs/input.md b/docs/input.md
index 0740adde50..64ec68d057 100644
--- a/docs/input.md
+++ b/docs/input.md
@@ -1,4 +1,4 @@
-# Input cheat sheet
+# Working with input
 
 ## Fill out the form, enter text
 ```js
@@ -23,11 +23,10 @@ await page.fill('#local', '2020-03-02T05:15');
 
 #### API reference
 
-- [`page.fill(selector, value[, options])`](https://github.com/microsoft/playwright/blob/master/docs/api.md#pagefillselector-value-options) — on the main frame
-- [`frame.fill(selector, value[, options])`](https://github.com/microsoft/playwright/blob/master/docs/api.md#framefillselector-value-options) — on a specific frame
-- [`elementHandle.fill(value[, options])`](https://github.com/microsoft/playwright/blob/master/docs/api.md#elementhandlefillvalue-options) — on a particular element
+- [`page.fill(selector, value[, options])`](./api.md#pagefillselector-value-options) — on the main frame
+- [`frame.fill(selector, value[, options])`](./api.md#framefillselector-value-options) — on a specific frame
+- [`elementHandle.fill(value[, options])`](./api.md#elementhandlefillvalue-options) — on a particular element
 
-<br/>
 <br/>
 
 ## Check / uncheck the checkbox
@@ -44,14 +43,13 @@ This is the easiest way to check and uncheck a checkbox. This method can be used
 
 #### API reference
 
-- [`page.check(selector[, options])`](https://github.com/microsoft/playwright/blob/master/docs/api.md#pagecheckselector-options) — on the main frame
-- [`page.uncheck(selector[, options])`](https://github.com/microsoft/playwright/blob/master/docs/api.md#pageuncheckselector-options) — on the main frame
-- [`frame.check(selector[, options])`](https://github.com/microsoft/playwright/blob/master/docs/api.md#framecheckselector-options) — on a specific frame
-- [`frame.uncheck(selector[, options])`](https://github.com/microsoft/playwright/blob/master/docs/api.md#frameuncheckselector-options) — on a specific frame
-- [`elementHandle.check(value[, options])`](https://github.com/microsoft/playwright/blob/master/docs/api.md#elementhandleuncheckoptions) — on a particular element
-- [`elementHandle.uncheck(value[, options])`](https://github.com/microsoft/playwright/blob/master/docs/api.md#elementhandleuncheckoptions) — on a particular element
+- [`page.check(selector[, options])`](./api.md#pagecheckselector-options) — on the main frame
+- [`page.uncheck(selector[, options])`](./api.md#pageuncheckselector-options) — on the main frame
+- [`frame.check(selector[, options])`](./api.md#framecheckselector-options) — on a specific frame
+- [`frame.uncheck(selector[, options])`](./api.md#frameuncheckselector-options) — on a specific frame
+- [`elementHandle.check(value[, options])`](./api.md#elementhandleuncheckoptions) — on a particular element
+- [`elementHandle.uncheck(value[, options])`](./api.md#elementhandleuncheckoptions) — on a particular element
 
-<br/>
 <br/>
 
 ## Select an option
@@ -88,11 +86,10 @@ page.selectOption('select#colors', option);
 
 #### API reference
 
-- [`page.selectOption(selector, values[, options])`](https://github.com/microsoft/playwright/blob/master/docs/api.md#pageselectoptionselector-values-options) — on the main frame
-- [`frame.selectOption(selector, values[, options])`](https://github.com/microsoft/playwright/blob/master/docs/api.md#frameselectoptionselector-values-options) — on a specific frame
-- [`elementHandle.selectOption(values[, options])`](https://github.com/microsoft/playwright/blob/master/docs/api.md#elementhandleselectoptionvalues-options) — on a particular element
+- [`page.selectOption(selector, values[, options])`](./api.md#pageselectoptionselector-values-options) — on the main frame
+- [`frame.selectOption(selector, values[, options])`](./api.md#frameselectoptionselector-values-options) — on a specific frame
+- [`elementHandle.selectOption(values[, options])`](./api.md#elementhandleselectoptionvalues-options) — on a particular element
 
-<br/>
 <br/>
 
 ## Type character by character
@@ -106,12 +103,11 @@ Sometimes it is important to type into the focused field character by character,
 
 #### API reference
 
-- [`page.type(selector, text[, options])`](https://github.com/microsoft/playwright/blob/master/docs/api.md#pagetypeselector-text-options) — on the main frame
-- [`frame.type(selector, text[, options])`](https://github.com/microsoft/playwright/blob/master/docs/api.md#frametypeselector-text-options) — on a specific frame
-- [`elementHandle.type(text[, options])`](https://github.com/microsoft/playwright/blob/master/docs/api.md#elementhandletypetext-options) — on a particular element
-- [`keyboard.type(text[, options])`](https://github.com/microsoft/playwright/blob/master/docs/api.md#keyboardtypetext-options) — wherever the current focus is
+- [`page.type(selector, text[, options])`](./api.md#pagetypeselector-text-options) — on the main frame
+- [`frame.type(selector, text[, options])`](./api.md#frametypeselector-text-options) — on a specific frame
+- [`elementHandle.type(text[, options])`](./api.md#elementhandletypetext-options) — on a particular element
+- [`keyboard.type(text[, options])`](./api.md#keyboardtypetext-options) — wherever the current focus is
 
-<br/>
 <br/>
 
 ## Press a key, enter keyboard shortcut
@@ -165,7 +161,7 @@ Note that you still need to specify the capital `A` in `Shift-A` to produce the
 
 #### API reference
 
-- [`page.press(selector, key[, options])`](https://github.com/microsoft/playwright/blob/master/docs/api.md#pagepressselector-key-options) — on the main frame
-- [`frame.press(selector, key[, options])`](https://github.com/microsoft/playwright/blob/master/docs/api.md#framepressselector-key-options) — on a specific frame
-- [`elementHandle.press(key[, options])`](https://github.com/microsoft/playwright/blob/master/docs/api.md#elementhandlepresskey-options) — on a particular element
-- [`keyboard.press(key[, options])`](https://github.com/microsoft/playwright/blob/master/docs/api.md#keyboardpresskey-options) — wherever the current focus is
+- [`page.press(selector, key[, options])`](./api.md#pagepressselector-key-options) — on the main frame
+- [`frame.press(selector, key[, options])`](./api.md#framepressselector-key-options) — on a specific frame
+- [`elementHandle.press(key[, options])`](./api.md#elementhandlepresskey-options) — on a particular element
+- [`keyboard.press(key[, options])`](./api.md#keyboardpresskey-options) — wherever the current focus is
diff --git a/docs/network.md b/docs/network.md
index f55b0402e3..326b06018a 100644
--- a/docs/network.md
+++ b/docs/network.md
@@ -1,7 +1,5 @@
 # Working With Network
 
-![playwright network](https://user-images.githubusercontent.com/746130/79428385-f0264900-7f7a-11ea-86e6-cd03190b8de7.png)
-
 Playwright provides APIs to **monitor** and **modify** network traffic, both HTTP and HTTPS.
 Any requests that page does, including [XHRs](https://developer.mozilla.org/en-US/docs/Web/API/XMLHttpRequest) and
 [fetch](https://developer.mozilla.org/en-US/docs/Web/API/Fetch_API) requests, can be tracked and modified.
@@ -13,26 +11,56 @@ Any requests that page does, including [XHRs](https://developer.mozilla.org/en-U
 ## Monitor all network activity in page
 
 ```js
-const page = await browser.newPage();
-page.on('request', request => console.log('>>', request.method(), request.url()));
-page.on('response', response => console.log('<<', response.status(), response.url()));
-await page.goto('https://example.com');
+const { chromium, webkit, firefox } = require('playwright');
+
+(async () => {
+  const browser = await chromium.launch();
+  const page = await browser.newPage();
+
+  // Subscribe to 'request' and 'response' events.S
+  page.on('request', request =>
+      console.log('>>', request.method(), request.url()));
+  page.on('response', response =>
+      console.log('<<', response.status(), response.url()));
+  await page.goto('https://example.com');
+
+  await browser.close();
+})();
 ```
 
 #### API reference
 
+- [`Request`](./api.md#class-request)
+- [`Response`](./api.md#class-response)
 - [`event: 'request'`](./api.md#event-request)
 - [`event: 'response'`](./api.md#event-response)
-- [`request.method()`](./api.md#requestmethod)
-- [`request.url()`](./api.md#requesturl)
 
+<br/>
 
-## Wait for a response from API endpoint after button click
+## Wait for a network response after the button click
 
 ```js
 const [response] = await Promise.all([
   page.waitForResponse('/api/fetch_data'),
-  page.click('button[type=submit]'),
+  page.click('button#update'),
+]);
+```
+
+The snippet above clicks a button and waits for the network response that matches the given pattern.
+
+#### Variations
+
+```js
+// User glob URL pattern
+const [response] = await Promise.all([
+  page.waitForResponse('**/*'),
+  page.click('button#update'),
+]);
+
+// User pattern predicate
+const [response] = await Promise.all([
+  page.waitForResponse(url => url.includes(token)),
+  page.click('button#update'),
 ]);
 ```
 
@@ -41,9 +69,9 @@ const [response] = await Promise.all([
 - [`page.waitForRequest(urlOrPredicate[, options])`](./api.md#pagewaitforrequesturlorpredicate-options)
 - [`page.waitForResponse(urlOrPredicate[, options])`](./api.md#pagewaitforresponseurlorpredicate-options)
 
+<br/>
 
-
-## Mock API endpoint with test data
+## Mock API endpoint with the test data
 
 ```js
 await page.route('/api/fetch_data', route => route.fulfill({
@@ -56,15 +84,30 @@ await page.goto('https://example.com');
 You can also use [`browserContext.route`](./api.md#browsercontextrouteurl-handler) to mock
 API endpoints for all the pages in the context.
 
+#### Variations
+
+```js
+// Set up route on the entire browser context.
+// It will apply to popup windows and opened links.
+
+await browserContext.route('/api/login', route => route.fulfill({
+  status: 200,
+  body: 'accept',
+}));
+await page.goto('https://example.com');
+```
+
 #### API reference
 
-- [`page.route(url, handler)`](./api.md#pagerouteurl-handler)
 - [`browserContext.route(url, handler)`](./api.md#browsercontextrouteurl-handler)
-- [`route.fulfill(response)`](./api.md#routefulfillresponse)
+- [`browserContext.unroute(url[, handler])`](./api.md#browsercontextunrouteurl-handler)
+- [`page.route(url, handler)`](./api.md#pagerouteurl-handler)
+- [`page.unroute(url[, handler])`](./api.md#pageunrouteurl-handler)
+- [`Route`](./api.md#class-route)
 
+<br/>
 
-
-## Abort all images to speedup page load
+## Abort selected requests
 
 ```js
 const page = await browser.newPage();
@@ -72,8 +115,17 @@ await page.route('**/*.{png,jpg,jpeg}', route => route.abort());
 await page.goto('https://example.com');
 ```
 
-You can also use [`browserContext.route`](./api.md#browsercontextrouteurl-handler) to abort
-images for all pages in the context, including popups.
+#### Variations
+
+```js
+// Abort requests based on their type.
+
+await page.route('**/*', route => {
+  return route.request().resourceType() === 'image' ?
+      route.abort() : route.continue();
+});
+await page.goto('https://chromium.org');
+```
 
 #### API reference
 
@@ -81,7 +133,33 @@ images for all pages in the context, including popups.
 - [`browserContext.route(url, handler)`](./api.md#browsercontextrouteurl-handler)
 - [`route.abort([errorCode])`](./api.md#routeaborterrorcode)
 
+<br/>
 
+## Modify selected requests
+
+
+```js
+await page.route('**/*', route => {
+  const headers = route.request().headers();
+  delete headers['X-Secret'];
+  route.continue({headers});
+});
+await page.goto('https://chromium.org');
+```
+
+You can continue requests with modifications. Example above removes an HTTP header from the outgoing requests.
+
+#### Variations
+
+```js
+// Continue requests as POST.
+
+await page.route('**/*', route =>
+    route.continue({method: 'POST'}));
+await page.goto('https://chromium.org');
+```
+
+<br/>
 
 ## Setup [HTTP authentication](https://developer.mozilla.org/en-US/docs/Web/HTTP/Authentication)
 
diff --git a/src/network.ts b/src/network.ts
index 99a76d8427..5e9efcacdd 100644
--- a/src/network.ts
+++ b/src/network.ts
@@ -151,7 +151,7 @@ export class Request {
   }
 
   headers(): {[key: string]: string} {
-    return this._headers;
+    return { ...this._headers };
   }
 
   response(): Promise<Response | null> {
@@ -291,7 +291,7 @@ export class Response {
   }
 
   headers(): object {
-    return this._headers;
+    return { ...this._headers };
   }
 
   finished(): Promise<Error | null> {