fix(emulation): sync navigator.platform with custom user agent across all browsers#39723
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manimovassagh wants to merge 4 commits intomicrosoft:mainfrom
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fix(emulation): sync navigator.platform with custom user agent across all browsers#39723manimovassagh wants to merge 4 commits intomicrosoft:mainfrom
manimovassagh wants to merge 4 commits intomicrosoft:mainfrom
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Updated the PR with both changes: 1. 2. Firefox and WebKit support
Added a shared Tested locally on Chromium, Firefox, and WebKit — all passing. |
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… all browsers When a custom userAgent is configured (e.g. via device presets), Playwright sends platform metadata via CDP/protocol but does not override navigator.platform. This causes navigator.platform to leak the host OS while the emulated platform reflects the user agent string. Pass the platform parameter in Emulation.setUserAgentOverride (Chromium), Browser.setPlatformOverride (Firefox), and Page.overridePlatform (WebKit). The new behavior can be disabled by setting PLAYWRIGHT_NO_UA_PLATFORM=1. Fixes microsoft#39568
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Test results for "MCP"1 failed 5338 passed, 186 skipped Merge workflow run. |
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Test results for "tests 1"2 failed 6 flaky38806 passed, 845 skipped Merge workflow run. |
dgozman
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…ion in browserContext Consolidates calculateUserAgentMetadata (crPage.ts) and navigatorPlatformFromUA (browserContext.ts) into a single calculateUserAgentEmulation() exported from browserContext.ts. All three browsers now call this one function which also handles the PLAYWRIGHT_NO_UA_PLATFORM check internally. Removes the duplicated env-var checks from crPage.ts, ffBrowser.ts, and wkPage.ts.
…acOS UA strings encode version as e.g. "iPhone OS 16_6" but Chromium Client Hints platformVersion expects "16.6". Apply replace(/_/g, '.') for iOS and macOS matches.
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When a custom
userAgentis configured (e.g. via device presets likeDesktop Chrome),navigator.platformleaks the host OS instead of matching the emulated user agent:navigator.userAgentData.platform→"Windows"(from the preset UA)navigator.platform→"MacIntel"(host OS leaked)Libraries like React Aria check
userAgentData.platformfirst, get"Windows", andthen expect Windows keyboard behavior — breaking tests that use
ControlOrMeta.Changes
Per @dgozman's request, unified into a single
calculateUserAgentEmulation(options: BrowserContextOptions)inbrowserContext.tsthat returns:navigatorPlatform: string | undefineduserAgentMetadata: { mobile, model, architecture, platform, platformVersion } | undefinedThe
PLAYWRIGHT_NO_UA_PLATFORMcheck lives inside this function (not duplicated across call sites).Chromium (
crPage.ts): passesplatforminEmulation.setUserAgentOverrideviauserAgentMetadataFirefox (
ffBrowser.ts): callsBrowser.setPlatformOverridealongsideBrowser.setUserAgentOverrideWebKit (
wkPage.ts): callsPage.overridePlatformalongsidePage.overrideUserAgentplatformVersionis normalized: UA strings encode iOS/macOS versions with underscores (16_6) but Client Hints expect dots (16.6).When no custom user agent is set, behavior is unchanged. Set
PLAYWRIGHT_NO_UA_PLATFORM=1to opt out.Fixes #39568