fix(webkit): do not override Accept-Language header set by the page

packages/playwright-core/src/server/webkit/wkPage.ts

@@ -676,13 +676,10 @@ export class WKPage implements PageDelegate {
   }
 
   _calculateExtraHTTPHeaders(): types.HeadersArray {
-    const locale = this._browserContext._options.locale;
-    const headers = network.mergeHeaders([
+    return network.mergeHeaders([
       this._browserContext._options.extraHTTPHeaders,
       this._page.extraHTTPHeaders(),
-      locale ? network.singleHeader('Accept-Language', locale) : undefined,
     ]);
-    return headers;
   }
 
   async updateEmulateMedia(): Promise<void> {

tests/library/browsercontext-locale.spec.ts

@@ -192,8 +192,7 @@ it('should affect Intl.DateTimeFormat().resolvedOptions().locale', async ({ brow
 
 it('should send user Accept-Language header', {
   annotation: [{ type: 'issue', description: 'https://github.com/microsoft/playwright/issues/23732' }],
-}, async ({ browser, server, browserName }) => {
-  it.fixme(browserName === 'webkit', 'Implementation set Accept-Language header as extra HTTP header');
+}, async ({ browser, server }) => {
   const context = await browser.newContext({ locale: 'en-GB' });
   const page = await context.newPage();
   await page.goto(server.EMPTY_PAGE);
@@ -224,3 +223,17 @@ it('should send user Accept-Language header', {
   }
   await context.close();
 });
+
+it('should send Accept-Language header on WebSocket handshake', {
+  annotation: [{ type: 'issue', description: 'https://github.com/microsoft/playwright/issues/23732' }],
+}, async ({ browser, server, browserName }) => {
+  it.fixme(browserName === 'firefox', 'Firefox does not send Accept-Language on WebSocket handshake');
+  const context = await browser.newContext({ locale: 'en-GB' });
+  const page = await context.newPage();
+  await page.goto(server.EMPTY_PAGE);
+  const reqPromise = server.waitForWebSocketConnectionRequest();
+  await page.evaluate(port => { new WebSocket(`ws://localhost:${port}/ws`); }, server.PORT);
+  const req = await reqPromise;
+  expect(req.headers['accept-language']).toContain('en-GB');
+  await context.close();
+});