feat: remove nativeWindowOpen option (#29405)

Co-authored-by: Cheng Zhao <zcbenz@gmail.com>
Co-authored-by: Milan Burda <milan.burda@gmail.com>

docs/README.md

@@ -106,7 +106,6 @@ These individual tutorials expand on topics discussed in the guide above.
 * [`File` Object](api/file-object.md)
 * [`<webview>` Tag](api/webview-tag.md)
 * [`window.open` Function](api/window-open.md)
-* [`BrowserWindowProxy` Object](api/browser-window-proxy.md)
 
 ### Modules for the Main Process:
 

docs/api/browser-window.md

@@ -341,9 +341,6 @@ It creates a new `BrowserWindow` with native properties as set by the `options`.
       [Chrome Content Scripts][chrome-content-scripts].  You can access this
       context in the dev tools by selecting the 'Electron Isolated Context'
       entry in the combo box at the top of the Console tab.
-    * `nativeWindowOpen` boolean (optional) - Whether to use native
-      `window.open()`. Defaults to `true`. Child windows will always have node
-      integration disabled unless `nodeIntegrationInSubFrames` is true.
     * `webviewTag` boolean (optional) - Whether to enable the [`<webview>` tag](webview-tag.md).
       Defaults to `false`. **Note:** The
       `preload` script configured for the `<webview>` will have node integration

docs/api/structures/post-body.md

@@ -7,17 +7,3 @@
   the `enctype` attribute of the submitted HTML form.
 * `boundary` string (optional) - The boundary used to separate multiple parts of
   the message. Only valid when `contentType` is `multipart/form-data`.
-
-Note that keys starting with `--` are not currently supported. For example, this will errantly submit as `multipart/form-data` when `nativeWindowOpen` is set to `false` in webPreferences:
-
-```html
-<form
-  target="_blank"
-  method="POST"
-  enctype="application/x-www-form-urlencoded"
-  action="https://postman-echo.com/post"
->
-  <input type="text" name="--theKey">
-  <input type="submit">
-</form>
-```

docs/api/window-open.md

@@ -12,10 +12,6 @@ useful for app sub-windows that act as preference panels, or similar, as the
 parent can render to the sub-window directly, as if it were a `div` in the
 parent. This is the same behavior as in the browser.
 
-When `nativeWindowOpen` is set to false, `window.open` instead results in the
-creation of a [`BrowserWindowProxy`](browser-window-proxy.md), a light wrapper
-around `BrowserWindow`.
-
 Electron pairs this native Chrome `Window` with a BrowserWindow under the hood.
 You can take advantage of all the customization available when creating a
 BrowserWindow in the main process by using `webContents.setWindowOpenHandler()`
@@ -34,7 +30,7 @@ because it is invoked in the main process.
 * `frameName` string (optional)
 * `features` string (optional)
 
-Returns [`BrowserWindowProxy`](browser-window-proxy.md) | [`Window`](https://developer.mozilla.org/en-US/docs/Web/API/Window)
+Returns [`Window`](https://developer.mozilla.org/en-US/docs/Web/API/Window) | null
 
 `features` is a comma-separated key-value list, following the standard format of
 the browser. Electron will parse `BrowserWindowConstructorOptions` out of this
@@ -108,33 +104,3 @@ mainWindow.webContents.setWindowOpenHandler(({ url }) => {
 const childWindow = window.open('', 'modal')
 childWindow.document.write('<h1>Hello</h1>')
 ```
-
-### `BrowserWindowProxy` example
-
-```javascript
-
-// main.js
-const mainWindow = new BrowserWindow({
-  webPreferences: { nativeWindowOpen: false }
-})
-
-mainWindow.webContents.setWindowOpenHandler(({ url }) => {
-  if (url.startsWith('https://github.com/')) {
-    return { action: 'allow' }
-  }
-  return { action: 'deny' }
-})
-
-mainWindow.webContents.on('did-create-window', (childWindow) => {
-  // For example...
-  childWindow.webContents.on('will-navigate', (e) => {
-    e.preventDefault()
-  })
-})
-```
-
-```javascript
-// renderer.js
-const windowProxy = window.open('https://github.com/', null, 'minimizable=false')
-windowProxy.postMessage('hi', '*')
-```

docs/breaking-changes.md

@@ -12,6 +12,18 @@ This document uses the following convention to categorize breaking changes:
 * **Deprecated:** An API was marked as deprecated. The API will continue to function, but will emit a deprecation warning, and will be removed in a future release.
 * **Removed:** An API or feature was removed, and is no longer supported by Electron.
 
+## Planned Breaking API Changes (18.0)
+
+### Removed: `nativeWindowOpen`
+
+Prior to Electron 15, `window.open` was by default shimmed to use
+`BrowserWindowProxy`. This meant that `window.open('about:blank')` did not work
+to open synchronously scriptable child windows, among other incompatibilities.
+Since Electron 15, `nativeWindowOpen` has been enabled by default.
+
+See the documentation for [window.open in Electron](api/window-open.md)
+for more details.
+
 ## Planned Breaking API Changes (17.0)
 
 ### Removed: `desktopCapturer.getSources` in the renderer

filenames.auto.gni

@@ -5,7 +5,6 @@ auto_filenames = {
     "docs/api/app.md",
     "docs/api/auto-updater.md",
     "docs/api/browser-view.md",
-    "docs/api/browser-window-proxy.md",
     "docs/api/browser-window.md",
     "docs/api/client-request.md",
     "docs/api/clipboard.md",
@@ -226,7 +225,6 @@ auto_filenames = {
     "lib/browser/devtools.ts",
     "lib/browser/guest-view-manager.ts",
     "lib/browser/guest-window-manager.ts",
-    "lib/browser/guest-window-proxy.ts",
     "lib/browser/init.ts",
     "lib/browser/ipc-main-impl.ts",
     "lib/browser/ipc-main-internal-utils.ts",

lib/browser/api/web-contents.ts

@@ -692,8 +692,8 @@ WebContents.prototype._init = function () {
         // TODO(zcbenz): The features string is parsed twice: here where it is
         // passed to C++, and in |makeBrowserWindowOptions| later where it is
         // not actually used since the WebContents is created here.
-        // We should be able to remove the latter once the |nativeWindowOpen|
-        // option is removed.
+        // We should be able to remove the latter once the |new-window| event
+        // is removed.
         const { webPreferences: parsedWebPreferences } = parseFeatures(rawFeatures);
         // Parameters should keep same with |makeBrowserWindowOptions|.
         const webPreferences = makeWebPreferences({
@@ -705,8 +705,7 @@ WebContents.prototype._init = function () {
       }
     });
 
-    // Create a new browser window for the native implementation of
-    // "window.open", used in sandbox and nativeWindowOpen mode.
+    // Create a new browser window for "window.open"
     this.on('-add-new-contents' as any, (event: ElectronInternal.Event, webContents: Electron.WebContents, disposition: string,
       _userGesture: boolean, _left: number, _top: number, _width: number, _height: number, url: string, frameName: string,
       referrer: Electron.Referrer, rawFeatures: string, postData: PostData) => {

lib/browser/guest-view-manager.ts

@@ -56,7 +56,6 @@ function makeWebPreferences (embedder: Electron.WebContents, params: Record<stri
   const inheritedWebPreferences = new Map([
     ['contextIsolation', true],
     ['javascript', false],
-    ['nativeWindowOpen', true],
     ['nodeIntegration', false],
     ['sandbox', true],
     ['nodeIntegrationInSubFrames', false],

lib/browser/guest-window-manager.ts

@@ -1,14 +1,13 @@
 /**
  * Create and minimally track guest windows at the direction of the renderer
  * (via window.open). Here, "guest" roughly means "child" — it's not necessarily
- * emblematic of its process status; both in-process (same-origin
- * nativeWindowOpen) and out-of-process (cross-origin nativeWindowOpen and
- * BrowserWindowProxy) are created here. "Embedder" roughly means "parent."
+ * emblematic of its process status; both in-process (same-origin) and
+ * out-of-process (cross-origin) are created here. "Embedder" roughly means
+ * "parent."
  */
 import { BrowserWindow } from 'electron/main';
 import type { BrowserWindowConstructorOptions, Referrer, WebContents, LoadURLOptions } from 'electron/main';
 import { parseFeatures } from '@electron/internal/browser/parse-features-string';
-import { IPC_MESSAGES } from '@electron/internal/common/ipc-messages';
 
 type PostData = LoadURLOptions['postData']
 export type WindowOpenArgs = {
@@ -23,13 +22,12 @@ const unregisterFrameName = (name: string) => frameNamesToWindow.delete(name);
 const getGuestWindowByFrameName = (name: string) => frameNamesToWindow.get(name);
 
 /**
- * `openGuestWindow` is called for both implementations of window.open
- * (BrowserWindowProxy and nativeWindowOpen) to create and setup event handling
- * for the new window.
+ * `openGuestWindow` is called to create and setup event handling for the new
+ * window.
  *
  * Until its removal in 12.0.0, the `new-window` event is fired, allowing the
  * user to preventDefault() on the passed event (which ends up calling
- * DestroyWebContents in the nativeWindowOpen code path).
+ * DestroyWebContents).
  */
 export function openGuestWindow ({ event, embedder, guest, referrer, disposition, postData, overrideBrowserWindowOptions, windowOpenArgs }: {
   event: { sender: WebContents, defaultPrevented: boolean },
@@ -78,22 +76,6 @@ export function openGuestWindow ({ event, embedder, guest, referrer, disposition
     webContents: guest,
     ...browserWindowOptions
   });
-  if (!guest) {
-    // We should only call `loadURL` if the webContents was constructed by us in
-    // the case of BrowserWindowProxy (non-sandboxed, nativeWindowOpen: false),
-    // as navigating to the url when creating the window from an existing
-    // webContents is not necessary (it will navigate there anyway).
-    // This can also happen if we enter this function from OpenURLFromTab, in
-    // which case the browser process is responsible for initiating navigation
-    // in the new window.
-    window.loadURL(url, {
-      httpReferrer: referrer,
-      ...(postData && {
-        postData,
-        extraHeaders: formatPostDataHeaders(postData as Electron.UploadRawData[])
-      })
-    });
-  }
 
   handleWindowLifecycleEvents({ embedder, frameName, guest: window });
 
@@ -118,9 +100,7 @@ const handleWindowLifecycleEvents = function ({ embedder, guest, frameName }: {
     guest.destroy();
   };
 
-  const cachedGuestId = guest.webContents.id;
   const closedByUser = function () {
-    embedder._sendInternal(`${IPC_MESSAGES.GUEST_WINDOW_MANAGER_WINDOW_CLOSED}_${cachedGuestId}`);
     embedder.removeListener('current-render-view-deleted' as any, closedByEmbedder);
   };
   embedder.once('current-render-view-deleted' as any, closedByEmbedder);
@@ -195,7 +175,6 @@ function emitDeprecatedNewWindowEvent ({ event, embedder, guest, windowOpenArgs,
 const securityWebPreferences: { [key: string]: boolean } = {
   contextIsolation: true,
   javascript: false,
-  nativeWindowOpen: true,
   nodeIntegration: false,
   sandbox: true,
   webviewTag: false,
@@ -217,10 +196,10 @@ function makeBrowserWindowOptions ({ embedder, features, overrideOptions }: {
       height: 600,
       ...parsedOptions,
       ...overrideOptions,
-      // Note that for |nativeWindowOpen: true| the WebContents is created in
-      // |api::WebContents::WebContentsCreatedWithFullParams|, with prefs
-      // parsed in the |-will-add-new-contents| event.
-      // The |webPreferences| here is only used by |nativeWindowOpen: false|.
+      // Note that for normal code path an existing WebContents created by
+      // Chromium will be used, with web preferences parsed in the
+      // |-will-add-new-contents| event.
+      // The |webPreferences| here is only used by the |new-window| event.
       webPreferences: makeWebPreferences({
         embedder,
         insecureParsedWebPreferences: parsedWebPreferences,
@@ -245,30 +224,17 @@ export function makeWebPreferences ({ embedder, secureOverrideWebPreferences = {
     }
     return map;
   }, {} as Electron.WebPreferences));
-  const openerId = parentWebPreferences.nativeWindowOpen ? null : embedder.id;
 
   return {
     ...parsedWebPreferences,
     // Note that order is key here, we want to disallow the renderer's
     // ability to change important security options but allow main (via
     // setWindowOpenHandler) to change them.
     ...securityWebPreferencesFromParent,
-    ...secureOverrideWebPreferences,
-    // Sets correct openerId here to give correct options to 'new-window' event handler
-    // TODO: Figure out another way to pass this?
-    openerId
+    ...secureOverrideWebPreferences
   };
 }
 
-function formatPostDataHeaders (postData: PostData) {
-  if (!postData) return;
-
-  const { contentType, boundary } = parseContentTypeFormat(postData);
-  if (boundary != null) { return `content-type: ${contentType}; boundary=${boundary}`; }
-
-  return `content-type: ${contentType}`;
-}
-
 const MULTIPART_CONTENT_TYPE = 'multipart/form-data';
 const URL_ENCODED_CONTENT_TYPE = 'application/x-www-form-urlencoded';