diff --git a/docs/src/api/class-elementhandle.md b/docs/src/api/class-elementhandle.md
index 223fa7aa5e..ba643d7fdf 100644
--- a/docs/src/api/class-elementhandle.md
+++ b/docs/src/api/class-elementhandle.md
@@ -66,6 +66,7 @@ expect(await tweetHandle.$eval('.retweets', node => node.innerText)).toBe('10');
 ### param: ElementHandle.$eval.selector = %%-query-selector-%%
 
 ### param: ElementHandle.$eval.pageFunction
+* langs: js
 - `pageFunction` <[function]\([Element]\)>
 
 Function to be evaluated in browser context
@@ -106,6 +107,7 @@ expect(await feedHandle.$$eval('.tweet', nodes => nodes.map(n => n.innerText))).
 ### param: ElementHandle.$$eval.selector = %%-query-selector-%%
 
 ### param: ElementHandle.$$eval.pageFunction
+* langs: js
 - `pageFunction` <[function]\([Array]<[Element]>\)>
 
 Function to be evaluated in browser context
diff --git a/docs/src/api/class-frame.md b/docs/src/api/class-frame.md
index e51f30fe7e..f16872ae80 100644
--- a/docs/src/api/class-frame.md
+++ b/docs/src/api/class-frame.md
@@ -86,6 +86,7 @@ const html = await frame.$eval('.main-container', (e, suffix) => e.outerHTML + s
 ### param: Frame.$eval.selector = %%-query-selector-%%
 
 ### param: Frame.$eval.pageFunction
+* langs: js
 - `pageFunction` <[function]\([Element]\)>
 
 Function to be evaluated in browser context
@@ -118,6 +119,7 @@ const divsCounts = await frame.$$eval('div', (divs, min) => divs.length >= min,
 ### param: Frame.$$eval.selector = %%-query-selector-%%
 
 ### param: Frame.$$eval.pageFunction
+* langs: js
 - `pageFunction` <[function]\([Array]<[Element]>\)>
 
 Function to be evaluated in browser context
@@ -134,12 +136,25 @@ Returns the added tag when the script's onload fires or when the script content
 
 Adds a `<script>` tag into the page with the desired url or content.
 
-### param: Frame.addScriptTag.params
-- `params` <[Object]>
-  - `url` <[string]> URL of a script to be added. Optional.
-  - `path` <[path]> Path to the JavaScript file to be injected into frame. If `path` is a relative path, then it is resolved relative to the current working directory. Optional.
-  - `content` <[string]> Raw JavaScript content to be injected into frame. Optional.
-  - `type` <[string]> Script type. Use 'module' in order to load a Javascript ES6 module. See [script](https://developer.mozilla.org/en-US/docs/Web/HTML/Element/script) for more details. Optional.
+### option: Frame.addScriptTag.url
+- `url` <[string]>
+
+URL of a script to be added.
+
+### option: Frame.addScriptTag.path
+- `path` <[path]>
+
+Path to the JavaScript file to be injected into frame. If `path` is a relative path, then it is resolved relative to the current working directory.
+
+### option: Frame.addScriptTag.content
+- `content` <[string]>
+
+Raw JavaScript content to be injected into frame.
+
+### option: Frame.addScriptTag.type
+- `type` <[string]>
+
+Script type. Use 'module' in order to load a Javascript ES6 module. See [script](https://developer.mozilla.org/en-US/docs/Web/HTML/Element/script) for more details.
 
 ## async method: Frame.addStyleTag
 - returns: <[ElementHandle]>
@@ -149,11 +164,20 @@ Returns the added tag when the stylesheet's onload fires or when the CSS content
 Adds a `<link rel="stylesheet">` tag into the page with the desired url or a `<style type="text/css">` tag with the
 content.
 
-### param: Frame.addStyleTag.params
-- `params` <[Object]>
-  - `url` <[string]> URL of the `<link>` tag. Optional.
-  - `path` <[path]> Path to the CSS file to be injected into frame. If `path` is a relative path, then it is resolved relative to the current working directory. Optional.
-  - `content` <[string]> Raw CSS content to be injected into frame. Optional.
+### option: Frame.addStyleTag.url
+- `url` <[string]>
+
+URL of the `<link>` tag.
+
+### option: Frame.addStyleTag.path
+- `path` <[path]>
+
+Path to the CSS file to be injected into frame. If `path` is a relative path, then it is resolved relative to the current working directory.
+
+### option: Frame.addStyleTag.content
+- `content` <[string]>
+
+Raw CSS content to be injected into frame.
 
 ## async method: Frame.check
 
@@ -324,6 +348,7 @@ await bodyHandle.dispose();
 ```
 
 ### param: Frame.evaluate.pageFunction
+* langs: js
 - `pageFunction` <[function]|[string]>
 
 Function to be evaluated in browser context
@@ -365,6 +390,7 @@ await resultHandle.dispose();
 ```
 
 ### param: Frame.evaluateHandle.pageFunction
+* langs: js
 - `pageFunction` <[function]|[string]>
 
 Function to be evaluated in the page context
@@ -790,6 +816,7 @@ await frame.waitForFunction(selector => !!document.querySelector(selector), sele
 ```
 
 ### param: Frame.waitForFunction.pageFunction
+* langs: js
 - `pageFunction` <[function]|[string]>
 
 Function to be evaluated in browser context
diff --git a/docs/src/api/class-jshandle.md b/docs/src/api/class-jshandle.md
index c37c7ccd2a..4067698bbd 100644
--- a/docs/src/api/class-jshandle.md
+++ b/docs/src/api/class-jshandle.md
@@ -42,6 +42,7 @@ expect(await tweetHandle.evaluate((node, suffix) => node.innerText, ' retweets')
 ```
 
 ### param: JSHandle.evaluate.pageFunction
+* langs: js
 - `pageFunction` <[function]>
 
 Function to be evaluated in browser context
@@ -67,6 +68,7 @@ for the promise to resolve and return its value.
 See [`method: Page.evaluateHandle`] for more details.
 
 ### param: JSHandle.evaluateHandle.pageFunction
+* langs: js
 - `pageFunction` <[function]|[string]>
 
 Function to be evaluated
diff --git a/docs/src/api/class-page.md b/docs/src/api/class-page.md
index ea67a9e875..6397d42135 100644
--- a/docs/src/api/class-page.md
+++ b/docs/src/api/class-page.md
@@ -258,6 +258,7 @@ Shortcut for main frame's [`method: Frame.$eval`].
 ### param: Page.$eval.selector = %%-query-selector-%%
 
 ### param: Page.$eval.pageFunction
+* langs: js
 - `pageFunction` <[function]\([Element]\)>
 
 Function to be evaluated in browser context
@@ -287,6 +288,7 @@ const divsCounts = await page.$$eval('div', (divs, min) => divs.length >= min, 1
 ### param: Page.$$eval.selector = %%-query-selector-%%
 
 ### param: Page.$$eval.pageFunction
+* langs: js
 - `pageFunction` <[function]\([Array]<[Element]>\)>
 
 Function to be evaluated in browser context
@@ -344,12 +346,25 @@ fires or when the script content was injected into frame.
 
 Shortcut for main frame's [`method: Frame.addScriptTag`].
 
-### param: Page.addScriptTag.params
-- `params` <[Object]>
-  - `url` <[string]> URL of a script to be added. Optional.
-  - `path` <[path]> Path to the JavaScript file to be injected into frame. If `path` is a relative path, then it is resolved relative to the current working directory. Optional.
-  - `content` <[string]> Raw JavaScript content to be injected into frame. Optional.
-  - `type` <[string]> Script type. Use 'module' in order to load a Javascript ES6 module. See [script](https://developer.mozilla.org/en-US/docs/Web/HTML/Element/script) for more details. Optional.
+### option: Page.addScriptTag.url
+- `url` <[string]>
+
+URL of a script to be added.
+
+### option: Page.addScriptTag.path
+- `path` <[path]>
+
+Path to the JavaScript file to be injected into frame. If `path` is a relative path, then it is resolved relative to the current working directory.
+
+### option: Page.addScriptTag.content
+- `content` <[string]>
+
+Raw JavaScript content to be injected into frame.
+
+### option: Page.addScriptTag.type
+- `type` <[string]>
+
+Script type. Use 'module' in order to load a Javascript ES6 module. See [script](https://developer.mozilla.org/en-US/docs/Web/HTML/Element/script) for more details.
 
 ## async method: Page.addStyleTag
 - returns: <[ElementHandle]>
@@ -359,11 +374,20 @@ content. Returns the added tag when the stylesheet's onload fires or when the CS
 
 Shortcut for main frame's [`method: Frame.addStyleTag`].
 
-### param: Page.addStyleTag.params
-- `params` <[Object]>
-  - `url` <[string]> URL of the `<link>` tag. Optional.
-  - `path` <[path]> Path to the CSS file to be injected into frame. If `path` is a relative path, then it is resolved relative to the current working directory. Optional.
-  - `content` <[string]> Raw CSS content to be injected into frame. Optional.
+### option: Page.addStyleTag.url
+- `url` <[string]>
+
+URL of the `<link>` tag.
+
+### option: Page.addStyleTag.path
+- `path` <[path]>
+
+Path to the CSS file to be injected into frame. If `path` is a relative path, then it is resolved relative to the current working directory.
+
+### option: Page.addStyleTag.content
+- `content` <[string]>
+
+Raw CSS content to be injected into frame.
 
 ## async method: Page.bringToFront
 
@@ -613,6 +637,7 @@ await bodyHandle.dispose();
 Shortcut for main frame's [`method: Frame.evaluate`].
 
 ### param: Page.evaluate.pageFunction
+* langs: js
 - `pageFunction` <[function]|[string]>
 
 Function to be evaluated in the page context
@@ -649,6 +674,7 @@ await resultHandle.dispose();
 ```
 
 ### param: Page.evaluateHandle.pageFunction
+* langs: js
 - `pageFunction` <[function]|[string]>
 
 Function to be evaluated in the page context
@@ -1615,6 +1641,7 @@ await page.waitForFunction(selector => !!document.querySelector(selector), selec
 Shortcut for main frame's [`method: Frame.waitForFunction`].
 
 ### param: Page.waitForFunction.pageFunction
+* langs: js
 - `pageFunction` <[function]|[string]>
 
 Function to be evaluated in browser context
diff --git a/docs/src/api/class-route.md b/docs/src/api/class-route.md
index 0b21cd3a96..c5d7ddf100 100644
--- a/docs/src/api/class-route.md
+++ b/docs/src/api/class-route.md
@@ -44,14 +44,26 @@ await page.route('**/*', (route, request) => {
 });
 ```
 
-### param: Route.continue.overrides
-- `overrides` <[Object]>
-  - `url` <[string]> If set changes the request URL. New URL must have same protocol as original one.
-  - `method` <[string]> If set changes the request method (e.g. GET or POST)
-  - `postData` <[string]|[Buffer]> If set changes the post data of request
-  - `headers` <[Object]<[string], [string]>> If set changes the request HTTP headers. Header values will be converted to a string.
+### option: Route.continue.url
+- `url` <[string]>
+
+If set changes the request URL. New URL must have same protocol as original one.
+
+### option: Route.continue.method
+- `method` <[string]>
+
+If set changes the request method (e.g. GET or POST)
+
+### option: Route.continue.postData
+- `postData` <[string]|[Buffer]>
+
+If set changes the post data of request
+
+### option: Route.continue.headers
+- `headers` <[Object]<[string], [string]>>
+
+If set changes the request HTTP headers. Header values will be converted to a string.
 
-Optional request overrides, can override following properties:
 
 ## async method: Route.fulfill
 
@@ -75,15 +87,30 @@ An example of serving static file:
 await page.route('**/xhr_endpoint', route => route.fulfill({ path: 'mock_data.json' }));
 ```
 
-### param: Route.fulfill.response
-- `response` <[Object]>
-  - `status` <[int]> Response status code, defaults to `200`.
-  - `headers` <[Object]<[string], [string]>> Optional response headers. Header values will be converted to a string.
-  - `contentType` <[string]> If set, equals to setting `Content-Type` response header.
-  - `body` <[string]|[Buffer]> Optional response body.
-  - `path` <[path]> Optional file path to respond with. The content type will be inferred from file extension. If `path` is a relative path, then it is resolved relative to the current working directory.
+### option: Route.fulfill.status
+- `status` <[int]>
 
-Response that will fulfill this route's request.
+Response status code, defaults to `200`.
+
+### option: Route.fulfill.headers
+- `headers` <[Object]<[string], [string]>>
+
+Response headers. Header values will be converted to a string.
+
+### option: Route.fulfill.contentType
+- `contentType` <[string]>
+
+If set, equals to setting `Content-Type` response header.
+
+### option: Route.fulfill.body
+- `body` <[string]|[Buffer]>
+
+Response body.
+
+### option: Route.fulfill.path
+- `path` <[path]>
+
+File path to respond with. The content type will be inferred from file extension. If `path` is a relative path, then it is resolved relative to the current working directory.
 
 ## method: Route.request
 - returns: <[Request]>
diff --git a/docs/src/api/class-worker.md b/docs/src/api/class-worker.md
index ef6e3be75d..08cc3fdb84 100644
--- a/docs/src/api/class-worker.md
+++ b/docs/src/api/class-worker.md
@@ -33,6 +33,7 @@ If the function passed to the `worker.evaluate` returns a non-[Serializable] val
 `-0`, `NaN`, `Infinity`, `-Infinity`, and bigint literals.
 
 ### param: Worker.evaluate.pageFunction
+* langs: js
 - `pageFunction` <[function]|[string]>
 
 Function to be evaluated in the worker context
@@ -54,6 +55,7 @@ If the function passed to the `worker.evaluateHandle` returns a [Promise], then
 the promise to resolve and return its value.
 
 ### param: Worker.evaluateHandle.pageFunction
+* langs: js
 - `pageFunction` <[function]|[string]>
 
 Function to be evaluated in the page context
diff --git a/docs/src/api/params.md b/docs/src/api/params.md
index 5c4661003f..17106edb4f 100644
--- a/docs/src/api/params.md
+++ b/docs/src/api/params.md
@@ -316,6 +316,19 @@ Receives the event data and resolves to truthy value when the waiting should res
 Maximum time to wait for in milliseconds. Defaults to `30000` (30 seconds). Pass `0` to disable timeout.
 The default value can be changed by using the [`method: BrowserContext.setDefaultTimeout`].
 
+## python-evaluate-expression
+* langs: python
+- `expression` <string>
+
+JavaScript expression to be evaluated in the browser context. If it looks like a function declaration,
+it is interpreted as a function. Otherwise, evaluated as an expression.
+
+## python-evaluate-force-expression
+* langs: python
+- `force_expr` <boolean>
+
+Whether to treat given `expression` as JavaScript evaluate expression, even though it looks like an arrow function.
+Optional.
 
 ## shared-context-params-list
 - %%-context-option-acceptdownloads-%%
diff --git a/docs/src/api/python.md b/docs/src/api/python.md
index ee4dc404cb..3ee737b909 100644
--- a/docs/src/api/python.md
+++ b/docs/src/api/python.md
@@ -102,3 +102,37 @@ value. Optional.
 ### option: Page.waitForEvent.timeout = %%-python-wait-for-event-timeout-%%
 ### option: WebSocket.waitForEvent.predicate = %%-python-wait-for-event-predicate-%%
 ### option: WebSocket.waitForEvent.timeout = %%-python-wait-for-event-timeout-%%
+
+### param: ElementHandle.$eval.expression = %%-python-evaluate-expression-%%
+### param: ElementHandle.$$eval.expression = %%-python-evaluate-expression-%%
+### param: Frame.$eval.expression = %%-python-evaluate-expression-%%
+### param: Frame.$$eval.expression = %%-python-evaluate-expression-%%
+### param: Frame.evaluate.expression = %%-python-evaluate-expression-%%
+### param: Frame.evaluateHandle.expression = %%-python-evaluate-expression-%%
+### param: Frame.waitForFunction.expression = %%-python-evaluate-expression-%%
+### param: JSHandle.evaluate.expression = %%-python-evaluate-expression-%%
+### param: JSHandle.evaluateHandle.expression = %%-python-evaluate-expression-%%
+### param: Page.$eval.expression = %%-python-evaluate-expression-%%
+### param: Page.$$eval.expression = %%-python-evaluate-expression-%%
+### param: Page.evaluate.expression = %%-python-evaluate-expression-%%
+### param: Page.evaluateHandle.expression = %%-python-evaluate-expression-%%
+### param: Page.waitForFunction.expression = %%-python-evaluate-expression-%%
+### param: Worker.evaluate.expression = %%-python-evaluate-expression-%%
+### param: Worker.evaluateHandle.expression = %%-python-evaluate-expression-%%
+
+### param: ElementHandle.$eval.expression = %%-python-evaluate-force-expression-%%
+### param: ElementHandle.$$eval.expression = %%-python-evaluate-force-expression-%%
+### param: Frame.$eval.expression = %%-python-evaluate-force-expression-%%
+### param: Frame.$$eval.expression = %%-python-evaluate-force-expression-%%
+### param: Frame.evaluate.expression = %%-python-evaluate-force-expression-%%
+### param: Frame.evaluateHandle.expression = %%-python-evaluate-force-expression-%%
+### param: Frame.waitForFunction.expression = %%-python-evaluate-force-expression-%%
+### param: JSHandle.evaluate.expression = %%-python-evaluate-force-expression-%%
+### param: JSHandle.evaluateHandle.expression = %%-python-evaluate-force-expression-%%
+### param: Page.$eval.expression = %%-python-evaluate-force-expression-%%
+### param: Page.$$eval.expression = %%-python-evaluate-force-expression-%%
+### param: Page.evaluate.expression = %%-python-evaluate-force-expression-%%
+### param: Page.evaluateHandle.expression = %%-python-evaluate-force-expression-%%
+### param: Page.waitForFunction.expression = %%-python-evaluate-force-expression-%%
+### param: Worker.evaluate.expression = %%-python-evaluate-force-expression-%%
+### param: Worker.evaluateHandle.expression = %%-python-evaluate-force-expression-%%
diff --git a/src/client/frame.ts b/src/client/frame.ts
index a937e92316..3c78f67724 100644
--- a/src/client/frame.ts
+++ b/src/client/frame.ts
@@ -284,9 +284,9 @@ export class Frame extends ChannelOwner<channels.FrameChannel, channels.FrameIni
     return this._detached;
   }
 
-  async addScriptTag(params: { url?: string, path?: string, content?: string, type?: string }): Promise<ElementHandle> {
+  async addScriptTag(options: { url?: string, path?: string, content?: string, type?: string } = {}): Promise<ElementHandle> {
     return this._wrapApiCall(this._apiName('addScriptTag'), async () => {
-      const copy = { ...params };
+      const copy = { ...options };
       if (copy.path) {
         copy.content = (await fsReadFileAsync(copy.path)).toString();
         copy.content += '//# sourceURL=' + copy.path.replace(/\n/g, '');
@@ -295,9 +295,9 @@ export class Frame extends ChannelOwner<channels.FrameChannel, channels.FrameIni
     });
   }
 
-  async addStyleTag(params: { url?: string; path?: string; content?: string; }): Promise<ElementHandle> {
+  async addStyleTag(options: { url?: string; path?: string; content?: string; } = {}): Promise<ElementHandle> {
     return this._wrapApiCall(this._apiName('addStyleTag'), async () => {
-      const copy = { ...params };
+      const copy = { ...options };
       if (copy.path) {
         copy.content = (await fsReadFileAsync(copy.path)).toString();
         copy.content += '/*# sourceURL=' + copy.path.replace(/\n/g, '') + '*/';
diff --git a/src/client/network.ts b/src/client/network.ts
index e9595b8e0c..990ed99a9f 100644
--- a/src/client/network.ts
+++ b/src/client/network.ts
@@ -185,49 +185,49 @@ export class Route extends ChannelOwner<channels.RouteChannel, channels.RouteIni
     await this._channel.abort({ errorCode });
   }
 
-  async fulfill(response: { status?: number, headers?: Headers, contentType?: string, body?: string | Buffer, path?: string }) {
+  async fulfill(options: { status?: number, headers?: Headers, contentType?: string, body?: string | Buffer, path?: string } = {}) {
     let body = '';
     let isBase64 = false;
     let length = 0;
-    if (response.path) {
-      const buffer = await util.promisify(fs.readFile)(response.path);
+    if (options.path) {
+      const buffer = await util.promisify(fs.readFile)(options.path);
       body = buffer.toString('base64');
       isBase64 = true;
       length = buffer.length;
-    } else if (isString(response.body)) {
-      body = response.body;
+    } else if (isString(options.body)) {
+      body = options.body;
       isBase64 = false;
       length = Buffer.byteLength(body);
-    } else if (response.body) {
-      body = response.body.toString('base64');
+    } else if (options.body) {
+      body = options.body.toString('base64');
       isBase64 = true;
-      length = response.body.length;
+      length = options.body.length;
     }
 
     const headers: Headers = {};
-    for (const header of Object.keys(response.headers || {}))
-      headers[header.toLowerCase()] = String(response.headers![header]);
-    if (response.contentType)
-      headers['content-type'] = String(response.contentType);
-    else if (response.path)
-      headers['content-type'] = mime.getType(response.path) || 'application/octet-stream';
+    for (const header of Object.keys(options.headers || {}))
+      headers[header.toLowerCase()] = String(options.headers![header]);
+    if (options.contentType)
+      headers['content-type'] = String(options.contentType);
+    else if (options.path)
+      headers['content-type'] = mime.getType(options.path) || 'application/octet-stream';
     if (length && !('content-length' in headers))
       headers['content-length'] = String(length);
 
     await this._channel.fulfill({
-      status: response.status || 200,
+      status: options.status || 200,
       headers: headersObjectToArray(headers),
       body,
       isBase64
     });
   }
 
-  async continue(overrides: { url?: string, method?: string, headers?: Headers, postData?: string | Buffer } = {}) {
-    const postDataBuffer = isString(overrides.postData) ? Buffer.from(overrides.postData, 'utf8') : overrides.postData;
+  async continue(options: { url?: string, method?: string, headers?: Headers, postData?: string | Buffer } = {}) {
+    const postDataBuffer = isString(options.postData) ? Buffer.from(options.postData, 'utf8') : options.postData;
     await this._channel.continue({
-      url: overrides.url,
-      method: overrides.method,
-      headers: overrides.headers ? headersObjectToArray(overrides.headers) : undefined,
+      url: options.url,
+      method: options.method,
+      headers: options.headers ? headersObjectToArray(options.headers) : undefined,
       postData: postDataBuffer ? postDataBuffer.toString('base64') : undefined,
     });
   }
diff --git a/src/client/page.ts b/src/client/page.ts
index 3c670a030b..86244fbc1a 100644
--- a/src/client/page.ts
+++ b/src/client/page.ts
@@ -296,12 +296,12 @@ export class Page extends ChannelOwner<channels.PageChannel, channels.PageInitia
     return this._attributeToPage(() => this._mainFrame.$$(selector));
   }
 
-  async addScriptTag(params: { url?: string; path?: string; content?: string; type?: string; }): Promise<ElementHandle> {
-    return this._attributeToPage(() => this._mainFrame.addScriptTag(params));
+  async addScriptTag(options: { url?: string; path?: string; content?: string; type?: string; } = {}): Promise<ElementHandle> {
+    return this._attributeToPage(() => this._mainFrame.addScriptTag(options));
   }
 
-  async addStyleTag(params: { url?: string; path?: string; content?: string; }): Promise<ElementHandle> {
-    return this._attributeToPage(() => this._mainFrame.addStyleTag(params));
+  async addStyleTag(options: { url?: string; path?: string; content?: string; } = {}): Promise<ElementHandle> {
+    return this._attributeToPage(() => this._mainFrame.addStyleTag(options));
   }
 
   async exposeFunction(name: string, callback: Function) {
@@ -403,7 +403,7 @@ export class Page extends ChannelOwner<channels.PageChannel, channels.PageInitia
     });
   }
 
-  async emulateMedia(params: { media?: 'screen' | 'print' | null, colorScheme?: 'dark' | 'light' | 'no-preference' | null }) {
+  async emulateMedia(params: { media?: 'screen' | 'print' | null, colorScheme?: 'dark' | 'light' | 'no-preference' | null } = {}) {
     return this._wrapApiCall('page.emulateMedia', async () => {
       await this._channel.emulateMedia({
         media: params.media === null ? 'null' : params.media,
diff --git a/types/types.d.ts b/types/types.d.ts
index cf9e29f7c0..e594c10034 100644
--- a/types/types.d.ts
+++ b/types/types.d.ts
@@ -1309,30 +1309,30 @@ export interface Page {
    * 
    * Shortcut for main frame's
    * [frame.addScriptTag(…)](https://github.com/microsoft/playwright/blob/master/docs/api.md#frameaddscripttag).
-   * @param params 
+   * @param options 
    */
-  addScriptTag(params: {
+  addScriptTag(options?: {
     /**
-     * URL of a script to be added. Optional.
-     */
-    url?: string;
-
-    /**
-     * Path to the JavaScript file to be injected into frame. If `path` is a relative path, then it is resolved relative to the
-     * current working directory. Optional.
-     */
-    path?: string;
-
-    /**
-     * Raw JavaScript content to be injected into frame. Optional.
+     * Raw JavaScript content to be injected into frame.
      */
     content?: string;
 
+    /**
+     * Path to the JavaScript file to be injected into frame. If `path` is a relative path, then it is resolved relative to the
+     * current working directory.
+     */
+    path?: string;
+
     /**
      * Script type. Use 'module' in order to load a Javascript ES6 module. See
-     * [script](https://developer.mozilla.org/en-US/docs/Web/HTML/Element/script) for more details. Optional.
+     * [script](https://developer.mozilla.org/en-US/docs/Web/HTML/Element/script) for more details.
      */
     type?: string;
+
+    /**
+     * URL of a script to be added.
+     */
+    url?: string;
   }): Promise<ElementHandle>;
 
   /**
@@ -1341,24 +1341,24 @@ export interface Page {
    * 
    * Shortcut for main frame's
    * [frame.addStyleTag(…)](https://github.com/microsoft/playwright/blob/master/docs/api.md#frameaddstyletag).
-   * @param params 
+   * @param options 
    */
-  addStyleTag(params: {
+  addStyleTag(options?: {
     /**
-     * URL of the `<link>` tag. Optional.
+     * Raw CSS content to be injected into frame.
      */
-    url?: string;
+    content?: string;
 
     /**
      * Path to the CSS file to be injected into frame. If `path` is a relative path, then it is resolved relative to the
-     * current working directory. Optional.
+     * current working directory.
      */
     path?: string;
 
     /**
-     * Raw CSS content to be injected into frame. Optional.
+     * URL of the `<link>` tag.
      */
-    content?: string;
+    url?: string;
   }): Promise<ElementHandle>;
 
   /**
@@ -3501,30 +3501,30 @@ export interface Frame {
    * Returns the added tag when the script's onload fires or when the script content was injected into frame.
    * 
    * Adds a `<script>` tag into the page with the desired url or content.
-   * @param params 
+   * @param options 
    */
-  addScriptTag(params: {
+  addScriptTag(options?: {
     /**
-     * URL of a script to be added. Optional.
-     */
-    url?: string;
-
-    /**
-     * Path to the JavaScript file to be injected into frame. If `path` is a relative path, then it is resolved relative to the
-     * current working directory. Optional.
-     */
-    path?: string;
-
-    /**
-     * Raw JavaScript content to be injected into frame. Optional.
+     * Raw JavaScript content to be injected into frame.
      */
     content?: string;
 
+    /**
+     * Path to the JavaScript file to be injected into frame. If `path` is a relative path, then it is resolved relative to the
+     * current working directory.
+     */
+    path?: string;
+
     /**
      * Script type. Use 'module' in order to load a Javascript ES6 module. See
-     * [script](https://developer.mozilla.org/en-US/docs/Web/HTML/Element/script) for more details. Optional.
+     * [script](https://developer.mozilla.org/en-US/docs/Web/HTML/Element/script) for more details.
      */
     type?: string;
+
+    /**
+     * URL of a script to be added.
+     */
+    url?: string;
   }): Promise<ElementHandle>;
 
   /**
@@ -3532,24 +3532,24 @@ export interface Frame {
    * 
    * Adds a `<link rel="stylesheet">` tag into the page with the desired url or a `<style type="text/css">` tag with the
    * content.
-   * @param params 
+   * @param options 
    */
-  addStyleTag(params: {
+  addStyleTag(options?: {
     /**
-     * URL of the `<link>` tag. Optional.
+     * Raw CSS content to be injected into frame.
      */
-    url?: string;
+    content?: string;
 
     /**
      * Path to the CSS file to be injected into frame. If `path` is a relative path, then it is resolved relative to the
-     * current working directory. Optional.
+     * current working directory.
      */
     path?: string;
 
     /**
-     * Raw CSS content to be injected into frame. Optional.
+     * URL of the `<link>` tag.
      */
-    content?: string;
+    url?: string;
   }): Promise<ElementHandle>;
 
   /**
@@ -8855,13 +8855,13 @@ export interface Route {
    * });
    * ```
    * 
-   * @param overrides Optional request overrides, can override following properties:
+   * @param options 
    */
-  continue(overrides?: {
+  continue(options?: {
     /**
-     * If set changes the request URL. New URL must have same protocol as original one.
+     * If set changes the request HTTP headers. Header values will be converted to a string.
      */
-    url?: string;
+    headers?: { [key: string]: string; };
 
     /**
      * If set changes the request method (e.g. GET or POST)
@@ -8874,9 +8874,9 @@ export interface Route {
     postData?: string|Buffer;
 
     /**
-     * If set changes the request HTTP headers. Header values will be converted to a string.
+     * If set changes the request URL. New URL must have same protocol as original one.
      */
-    headers?: { [key: string]: string; };
+    url?: string;
   }): Promise<void>;
 
   /**
@@ -8900,18 +8900,13 @@ export interface Route {
    * await page.route('**\/xhr_endpoint', route => route.fulfill({ path: 'mock_data.json' }));
    * ```
    * 
-   * @param response Response that will fulfill this route's request.
+   * @param options 
    */
-  fulfill(response: {
+  fulfill(options?: {
     /**
-     * Response status code, defaults to `200`.
+     * Response body.
      */
-    status?: number;
-
-    /**
-     * Optional response headers. Header values will be converted to a string.
-     */
-    headers?: { [key: string]: string; };
+    body?: string|Buffer;
 
     /**
      * If set, equals to setting `Content-Type` response header.
@@ -8919,15 +8914,20 @@ export interface Route {
     contentType?: string;
 
     /**
-     * Optional response body.
+     * Response headers. Header values will be converted to a string.
      */
-    body?: string|Buffer;
+    headers?: { [key: string]: string; };
 
     /**
-     * Optional file path to respond with. The content type will be inferred from file extension. If `path` is a relative path,
-     * then it is resolved relative to the current working directory.
+     * File path to respond with. The content type will be inferred from file extension. If `path` is a relative path, then it
+     * is resolved relative to the current working directory.
      */
     path?: string;
+
+    /**
+     * Response status code, defaults to `200`.
+     */
+    status?: number;
   }): Promise<void>;
 
   /**