[Bug]: Microsoft SAML login closes page on Edge since 1.60; adding --enable-automation fixes regression

[NikkTod]

Version

1.60.0

Steps to reproduce

[Bug]: Microsoft SAML login closes page on Edge since 1.60; adding --enable-automation fixes regression

Version

Regression starts with Playwright 1.60.0.

• 1.59.1 — ✅ works
• 1.60.0 — ❌ fails
• later stable versions — ❌ fail
• latest @next / canary — ❌ fails
• 1.60.0 with --enable-automation explicitly added — ✅ works

Environment

• OS: Windows 10 win64
• Node.js: v22.13.0
• Browser: Microsoft Edge 151
• Browser configuration: channel: 'msedge'
• Edge is organization-managed through enterprise policies
• The same installed Edge binary/version is used for all Playwright versions tested
• Authentication: Microsoft Entra ID / login.microsoftonline.com SAML flow
• Playwright: Node.js / TypeScript

Description

After upgrading from Playwright 1.59.1 to 1.60.0, our Microsoft SAML authentication flow started closing the Playwright page immediately after the final Sign in action.

The application, machine and browser environment are unchanged.

The important finding is that explicitly restoring the Chromium/Edge launch argument:

--enable-automation

makes the authentication flow work again with Playwright 1.60.0.

This appears significant because --enable-automation was present in Playwright's Chromium launch arguments in 1.59.1 but is no longer present starting with 1.60.0.

Reproduction

Our Playwright configuration normally contains:

use: {
  channel: 'msedge',
}

The test navigates through our application authentication flow to:

https://login.microsoftonline.com/...

and performs the Microsoft login.

Simplified example:

await page.getByLabel('Password').fill(password);

await page
  .getByRole('button', { name: 'Sign in' })
  .click();

With Playwright 1.59.1, Microsoft completes the SAML redirect back to the application normally.

With Playwright 1.60.0 and every newer version tested, the click itself succeeds, but shortly afterwards Playwright reports that the page has been closed.

For diagnostics I added:

page.on('close', () => {
  console.log('PAGE CLOSED');
});

page.on('crash', () => {
  console.log('PAGE CRASHED');
});

browser?.on('disconnected', () => {
  console.log('BROWSER DISCONNECTED');
});

The observed event is:

PAGE CLOSED

The failure can subsequently surface as:

Target page, context or browser has been closed

depending on which Playwright operation is awaiting the page at that moment.

Originally this surfaced from waitForResponse(), but removing all response/token handling did not change the behavior. The page still closes after the Microsoft Sign in action.

Important finding / workaround

With Playwright 1.60.0, changing only the launch configuration to:

use: {
  channel: 'msedge',

  launchOptions: {
    args: ['--enable-automation'],
  },
}

fixes the issue.

The Microsoft SAML login and redirect then complete successfully.

Therefore the comparison is:

Same machine
Same managed Edge
Same Edge version
Same application
Same authentication flow

Playwright 1.59.1                         PASS
Playwright 1.60.0                         FAIL
Playwright > 1.60                         FAIL
Playwright @next                          FAIL

Playwright 1.60.0 + --enable-automation   PASS

I also tested whether the Edge-specific msForceBrowserSignIn feature was responsible by changing the corresponding --disable-features configuration.

That did not fix the issue.

Only restoring:

--enable-automation

has fixed it so far.

Expected behavior

Expected behavior

Microsoft SAML authentication should complete successfully after clicking Sign in, and the existing Edge page should continue the redirect back to the application without being closed.

This is the behavior observed with Playwright 1.59.1 and also with Playwright 1.60.0 when --enable-automation is explicitly restored.

Actual behavior

Actual behavior

Starting with Playwright 1.60.0, the page is closed during/after the Microsoft authentication redirect.

Adding --enable-automation restores the previous working behavior.

Additional context

The Microsoft Edge installation is controlled by organization enterprise policies, so changing the browser version is not possible.

However, this makes the regression comparison quite controlled: all Playwright versions are tested against the same Edge installation and version.

This seems potentially related to #41348, which reports a Playwright 1.60 regression around Microsoft Entra/OAuth cross-origin navigation and TargetClosedException.

The additional observation here is that the regression can be deterministically avoided by restoring --enable-automation.

It may be worth investigating whether removing --enable-automation in Playwright 1.60 changes Microsoft Edge behavior under enterprise policies during Entra/SAML authentication.

Additional context

No response

Environment

System:
  OS: Windows 11 10.0.26100
  CPU: (8) x64 Intel Xeon Processor (Cascadelake)
  Memory: 16.48 GB / 31.88 GB

Binaries:
  Node: 22.13.0 - C:\Program Files\nodejs\node.EXE
  npm: 10.9.2 - C:\Program Files\nodejs\npm.CMD

IDEs:
  VSCode: 1.100.0 - C:\Program Files\Microsoft VS Code\bin\code.CMD

npmPackages:
  @playwright/test: ^1.60.0 => 1.60.0
  playwright-bdd: ^9.2.0 => 9.2.0
  playwright-mail-reporter: ^0.0.10 => 0.0.10

[dcrousso]

unfortunately i could not reproduce the page close with Playwright 1.59.1 and Edge 151.0.4129.107 on macOS

i ran a self contained cross origin sign in redirect five times each in headed and headless mode, both normally and with ignoreDefaultArgs: ['--enable-automation'], all of which passed

this suggests the failure requires Windows enterprise policy or the real Entra flow

could you please run this inverse test on the affected machine and report whether Playwright 1.59.1 starts failing?

use: {
  channel: 'msedge',
  launchOptions: {
    ignoreDefaultArgs: ['--enable-automation'],
  },
}

[NikkTod]

Hi Devin Rousso (@dcrousso), thanks for the quick response.

I can confirm that on 1.59.1 if I add ignoreDefaultArgs: ['--enable-automation'] the login test starts to fail as context is closed unexpectedly.

I work in a bank, so Windows/Browser enterprise policy is applied.

[dcrousso]

could you please confirm whether the failing run uses headless: false?

if so, could you please also test headless: true without --enable-automation, then test the original headed configuration with --guest instead of --enable-automation?

headless mode blocks Chromium process handoff, while guest mode avoids Edge profile switching, so this should identify which behavior is closing the page

[dcrousso]

--enable-automation was removed as it's a single switch that affects a lot of different things in favor of instead enabling the specific things needed

if the above doesn't work, you can (as you already mentioned) provide --enable-automation to work around this for now

[NikkTod]

Devin Rousso (@dcrousso) We run our regresison in Teamcity with headless:true without --enable-automation (Linux machine with Chrome browser installed) and tests are passing without an issue.

But on our local machines we run tests with headless:false , so after Playwright 1.59.1 if we do not pass --enable-automation , we will not be able to login with the tests users as browser is closing unexpectedly.

We are ok to continue using --enable-automation, but I guess in future more and more questions will come around this topic for corporate browsers.

[PandaMagnus]

I'm seeing this exact behavior as well (although with the C# version of Playwright.) I added --enable-automation to my script, and it is now working in headed mode. I did not have an issue in headless. I'm in the same boat as NikkTod , adding the flag isn't a problem for me, but I do think it will raise a lot of questions for those of us in corporate environments (I know I beat my head on this issue on Friday before finding this issue just now.)

[yagiz-dev]

I can confirm this exact behavior on a nearly identical environment.

The workaround works great, thanks NikkTod 🙂. I can provide help with additional testing if needed.

• Edge version 153.0.4234.32, managed using enterprise policies
• Headed mode
• "@playwright/test": "^1.63.0"
• Windows 10 22H2 (OS Build 19045.7725)