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fix(mcp): do not close the browser twice when the client disconnects - #43174

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Pavel Feldman (pavelfeldman) merged 1 commit into
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pavelfeldman:fix-43098
Oct 6, 2026
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Pavel Feldman (pavelfeldman) merged 1 commit into
microsoft:mainfrom
pavelfeldman:fix-43098

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Summary

  • On stdin end, the MCP server closed its transport, which closed the browser, and the exit watchdog closed the browser at the same time. The second close force-killed the browser. Remove the 'end' handler, so the watchdog is the only shutdown path.
  • The 'end' handler also killed a pending browser_annotate client. That client now notices the exit of its parent by itself: it reads stdin, so the 'close' event fires.

Fixes #43098

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On stdin end, the MCP server closed its transport, which closed the
browser, and the exit watchdog closed the browser at the same time.
The second close force-killed the browser. Remove the 'end' handler,
so the watchdog is the only shutdown path.

The 'end' handler also killed a pending browser_annotate client. That
client now notices the exit of its parent by itself: it reads stdin,
so the 'close' event fires.

Fixes: microsoft#43098
@pavelfeldman
Pavel Feldman (pavelfeldman) merged commit d6158cd into microsoft:main Oct 6, 2026
16 of 17 checks passed
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Test results for "MCP"

1 failed
❌ [firefox] › mcp/idle-timeout.spec.ts:19 › closes the browser after the idle timeout and relaunches it on the next call @mcp-windows-latest-firefox

9047 passed, 1495 skipped


Merge workflow run.

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Hi, I'm the Playwright bot and I took a first look at the latest CI run.

🟢 The remaining failure is a confirmed pre-existing flake

The PR is clear. The exact Windows Firefox test has failed on several unrelated PRs, before this change.

Details

Overall assessment

This PR changes shutdown after stdin disconnect and parent-process exit. The failing test keeps the MCP client connected and instead waits for the existing 500 ms browser idle timer, so those changed shutdown paths are not active. Its relaunch raced a browser close and returned Target page, context or browser has been closed.

Pre-existing flake / infra

Triaged by the Playwright bot - agent run

Dmitry Gozman (dgozman) added a commit that referenced this pull request Oct 7, 2026
Pavel Feldman (pavelfeldman) pushed a commit to microsoft/playwright-mcp that referenced this pull request Oct 31, 2026
## ✨ Highlights

- **👥 Separate sessions in one browser** — work with multiple accounts
without sharing their cookies or storage. `browser_tabs` with `action:
"new"` now accepts `isolatedContext: "<name>"`: tabs with the same name
share a context, while different names stay isolated. Omit it or use
`"default"` for the default context. Cookie and storage tools operate on
the current tab's context.
([microsoft/playwright#43087](microsoft/playwright#43087))
- **🙈 Redact runtime values in URLs**
([#1791](#1791)) —
session and grant values minted at runtime cannot be listed in a secrets
file ahead of time. `--redact-url-params=access_token,code` (config
`redactUrlParams`, env `PLAYWRIGHT_MCP_REDACT_URL_PARAMS`) replaces the
named query and fragment parameter values with `<redacted>` in tool
responses. Like `secrets`, this is a convenience, not a security
feature. The extension also removes its connection token from the
connect page URL after reading it.
([microsoft/playwright#43258](microsoft/playwright#43258))
- **🔎 Bound find results**
([microsoft/playwright#42077](microsoft/playwright#42077))
— common search terms no longer have to fill the response with every
match. `browser_find` accepts a positive integer `maxResults`, returns
the first matching items with their context, and reports the total match
count. Omit it to keep returning all matches; ancestor paths are
unchanged.
([microsoft/playwright#42947](microsoft/playwright#42947))
- **🌐 Inspect requests across navigations**
([microsoft/playwright-cli#479](microsoft/playwright-cli#479))
— requests from the previous page are no longer lost as soon as a flow
navigates. `browser_network_requests` accepts `all: true` to include
retained history, keeping up to 200 requests from earlier navigations.
Request indexes stay stable across navigations for
`browser_network_request`. `browser_console_messages` also reports
counts consistent with its existing `all` option.
([microsoft/playwright#43526](microsoft/playwright#43526))
- **🎯 Use locators in your language**
([#1797](#1797)) —
element tools such as `browser_click` now accept JavaScript, Python,
Java and C# locators in `target`, alongside snapshot refs and CSS
selectors. Invalid targets get an actionable error, including a reminder
to pass the bare ref rather than `button [ref=e5]`.
([microsoft/playwright#43539](microsoft/playwright#43539))
- **📂 Skip unsupported workspace-root requests**
([#1798](#1798)) —
clients that advertise roots but cannot answer `roots/list` can stall
the first tool call. Pass `--ignore-roots` (config `ignoreRoots: true`,
env `PLAYWRIGHT_MCP_IGNORE_ROOTS=true`) to skip that request and use the
server's current working directory as the workspace root.
([microsoft/playwright#43532](microsoft/playwright#43532))
- **🍪 Delete cookies by domain and path** — deleting a cookie by name no
longer has to remove every cookie with that name.
`browser_cookie_delete` (opt-in via `--caps=storage`) accepts optional
`domain` and `path` filters to leave other domains and paths untouched.
([microsoft/playwright#43319](microsoft/playwright#43319))

## 🐛 Fixes

- `fix(mcp): allow combining time, text and textGone in
browser_wait_for` — when combined with a text condition, `time` is its
timeout (capped at 30 seconds), not a delay before checking it.
Supplying both `text` and `textGone` now waits for the first condition
to happen, rather than both in sequence.
([microsoft/playwright#43011](microsoft/playwright#43011))
- `fix(mcp): allow loopback hosts by default for all bind addresses` —
HTTP clients can connect through `localhost`, `127.0.0.1` or `[::1]`
regardless of the bind address. Other hosts still require
`--allowed-hosts`; binding to `0.0.0.0` prints a usable localhost URL.
([microsoft/playwright#42993](microsoft/playwright#42993))
- `fix(mcp): pass credentials from --proxy-server as proxy
username/password` — credentials embedded in the proxy URL are now
passed to the browser as proxy authentication settings.
([microsoft/playwright#43071](microsoft/playwright#43071))
- `fix(mcp): race browser_navigate_back against modal states` —
`browser_navigate_back` reports a dialog opened during history
navigation instead of timing out.
([microsoft/playwright#43252](microsoft/playwright#43252))
- `fix(mcp): normalize bare host URLs and loopback IP addresses` —
`browser_navigate` handles scheme-less hosts with ports and uses HTTP
for loopback addresses such as `127.0.0.1:3000` and `[::1]:3000`.
([microsoft/playwright#43264](microsoft/playwright#43264))
- `fix(mcp): do not close the browser twice when the client disconnects`
— stdio disconnects let the browser close gracefully instead of
force-killing it through a second close request. Dashboard annotation
processes also exit when their parent goes away.
([microsoft/playwright#43174](microsoft/playwright#43174))
- `fix(mcp): give each isolated client its own idle timer` — with HTTP
transport and `--isolated`, an idle client's context now expires even
while another client keeps the shared browser busy.
([microsoft/playwright#43527](microsoft/playwright#43527))
- `fix(mcp): apply route headers without bypassing origin filters` —
`browser_route` (opt-in via `--caps=network`) matches added request
header names case-insensitively, includes custom headers in mocked
responses, and preserves origin filters and other routes when modifying
request headers.
([microsoft/playwright#43227](microsoft/playwright#43227),
[microsoft/playwright#43244](microsoft/playwright#43244),
[microsoft/playwright#43637](microsoft/playwright#43637))
- `fix(mcp): correct cookie filtering and missing-domain errors` —
`browser_cookie_list` (opt-in via `--caps=storage`) matches domain and
path boundaries instead of unrelated names such as `notexample.com` or
`/apiary`. `browser_cookie_set` asks for an explicit `domain` when the
current page has no hostname, such as `about:blank`.
([microsoft/playwright#43316](microsoft/playwright#43316),
[microsoft/playwright#43368](microsoft/playwright#43368),
[microsoft/playwright#43318](microsoft/playwright#43318))
- `fix(mcp): accept Windows paths in browser_resume location` —
`browser_resume` (opt-in via `--caps=devtools`) no longer mistakes a
Windows drive-letter colon for the line-number separator.
([microsoft/playwright#43349](microsoft/playwright#43349))
- `fix(mcp): report run-code route handler exceptions once and verbatim`
— `browser_run_code_unsafe` reports a route handler's thrown value
without duplicating it or wrapping non-Error values in another error.
([microsoft/playwright#43203](microsoft/playwright#43203))
- `fix(extension): release debugger when attach completes after
connection close` — disconnecting while `browser_tabs` attaches to a new
tab no longer leaves that tab attached to the extension's debugger.
([microsoft/playwright#43025](microsoft/playwright#43025))
- `fix(chromium): close pages that crashed before connecting over CDP` —
connecting through `--cdp-endpoint` no longer stalls on an already
crashed or discarded page; those pages are omitted from the tab list.
([microsoft/playwright#43075](microsoft/playwright#43075))
- `fix(aria): skip text nodes that are not rendered` —
`browser_snapshot` and accessible names omit unrendered text, including
unslotted shadow-host text and text directly inside closed `<details>`.
([microsoft/playwright#43150](microsoft/playwright#43150))
- `fix(a11y): treat inert elements and content outside of modal dialogs
as hidden` — snapshots exclude inert content and content outside the
topmost modal `<dialog>`. Click and fill actions wait for targets to
stop being inert instead of silently misfiring.
([microsoft/playwright#43211](microsoft/playwright#43211))
- `fix(aria): do not count whitespace-only contributors as name sources`
— snapshots retain button names when whitespace around a hidden icon
previously caused the name to disappear.
([microsoft/playwright#43317](microsoft/playwright#43317))
- `fix(aria): resolve label references consistently` — snapshots and
role locators recognize tab- or newline-separated label IDs and labels
assigned through `ariaLabelledByElements`, while retaining
attribute-based labels in older browsers.
([microsoft/playwright#43361](microsoft/playwright#43361),
[microsoft/playwright#43577](microsoft/playwright#43577),
[microsoft/playwright#43722](microsoft/playwright#43722))
- `fix(aria): quote ~, .inf and .nan in aria snapshots` — YAML-like
names remain strings rather than being parsed as null or special
floating-point values.
([microsoft/playwright#43469](microsoft/playwright#43469))
- `fix(aria): preserve iframe snapshots with fallback text` — snapshots
retain an iframe's contents when the iframe element also contains
fallback text.
([microsoft/playwright#43635](microsoft/playwright#43635))
- `fix(aria): match mixed-case roles and states` — snapshots and role
locators recognize mixed-case `role` and ARIA state values, including
checked, pressed and expanded states.
([microsoft/playwright#43727](microsoft/playwright#43727))

## 📦 Upgrading

Configs that use `@playwright/mcp@latest` pick this release up on the
next client restart. To pin it:

```bash
npx @playwright/mcp@0.0.84
```

Co-authored-by: microsoft-playwright-automation[bot] <203992400+microsoft-playwright-automation[bot]@users.noreply.github.com>
Paul Sorensen (paulnsorensen) added a commit to paulnsorensen/dotfiles that referenced this pull request Oct 31, 2026
This PR contains the following updates:

| Package | Change |
[Age](https://docs.renovatebot.com/merge-confidence/) |
[Adoption](https://docs.renovatebot.com/merge-confidence/) |
[Passing](https://docs.renovatebot.com/merge-confidence/) |
[Confidence](https://docs.renovatebot.com/merge-confidence/) |
|---|---|---|---|---|---|
| [@playwright/mcp](https://playwright.dev)
([source](https://redirect.github.com/microsoft/playwright-mcp)) |
`0.0.83` → `0.0.84` |
![age](https://developer.mend.io/api/mc/badges/age/npm/@playwright%2fmcp/0.0.84?slim=true)
|
![adoption](https://developer.mend.io/api/mc/badges/adoption/npm/@playwright%2fmcp/0.0.84?slim=true)
|
![passing](https://developer.mend.io/api/mc/badges/compatibility/npm/@playwright%2fmcp/0.0.83/0.0.84?slim=true)
|
![confidence](https://developer.mend.io/api/mc/badges/confidence/npm/@playwright%2fmcp/0.0.83/0.0.84?slim=true)
|

---

> [!WARNING]
> Some dependencies could not be looked up. Check the warning logs for
more information.

---

### Release Notes

<details>
<summary>microsoft/playwright-mcp (@&#8203;playwright/mcp)</summary>

###
[`v0.0.84`](https://redirect.github.com/microsoft/playwright-mcp/releases/tag/v0.0.84)

[Compare
Source](https://redirect.github.com/microsoft/playwright-mcp/compare/v0.0.83...v0.0.84)

#### ✨ Highlights

- **👥 Separate sessions in one browser** — work with multiple accounts
without sharing their cookies or storage. `browser_tabs` with `action:
"new"` now accepts `isolatedContext: "<name>"`: tabs with the same name
share a context, while different names stay isolated. Omit it or use
`"default"` for the default context. Cookie and storage tools operate on
the current tab's context.
([microsoft/playwright#43087](https://redirect.github.com/microsoft/playwright/pull/43087))
- **🙈 Redact runtime values in URLs**
([#&#8203;1791](https://redirect.github.com/microsoft/playwright-mcp/issues/1791))
— session and grant values minted at runtime cannot be listed in a
secrets file ahead of time. `--redact-url-params=access_token,code`
(config `redactUrlParams`, env `PLAYWRIGHT_MCP_REDACT_URL_PARAMS`)
replaces the named query and fragment parameter values with `<redacted>`
in tool responses. Like `secrets`, this is a convenience, not a security
feature. The extension also removes its connection token from the
connect page URL after reading it.
([microsoft/playwright#43258](https://redirect.github.com/microsoft/playwright/pull/43258))
- **🔎 Bound find results**
([microsoft/playwright#42077](https://redirect.github.com/microsoft/playwright/issues/42077))
— common search terms no longer have to fill the response with every
match. `browser_find` accepts a positive integer `maxResults`, returns
the first matching items with their context, and reports the total match
count. Omit it to keep returning all matches; ancestor paths are
unchanged.
([microsoft/playwright#42947](https://redirect.github.com/microsoft/playwright/pull/42947))
- **🌐 Inspect requests across navigations**
([microsoft/playwright-cli#479](https://redirect.github.com/microsoft/playwright-cli/issues/479))
— requests from the previous page are no longer lost as soon as a flow
navigates. `browser_network_requests` accepts `all: true` to include
retained history, keeping up to 200 requests from earlier navigations.
Request indexes stay stable across navigations for
`browser_network_request`. `browser_console_messages` also reports
counts consistent with its existing `all` option.
([microsoft/playwright#43526](https://redirect.github.com/microsoft/playwright/pull/43526))
- **🎯 Use locators in your language**
([#&#8203;1797](https://redirect.github.com/microsoft/playwright-mcp/issues/1797))
— element tools such as `browser_click` now accept JavaScript, Python,
Java and C# locators in `target`, alongside snapshot refs and CSS
selectors. Invalid targets get an actionable error, including a reminder
to pass the bare ref rather than `button [ref=e5]`.
([microsoft/playwright#43539](https://redirect.github.com/microsoft/playwright/pull/43539))
- **📂 Skip unsupported workspace-root requests**
([#&#8203;1798](https://redirect.github.com/microsoft/playwright-mcp/issues/1798))
— clients that advertise roots but cannot answer `roots/list` can stall
the first tool call. Pass `--ignore-roots` (config `ignoreRoots: true`,
env `PLAYWRIGHT_MCP_IGNORE_ROOTS=true`) to skip that request and use the
server's current working directory as the workspace root.
([microsoft/playwright#43532](https://redirect.github.com/microsoft/playwright/pull/43532))
- **🍪 Delete cookies by domain and path** — deleting a cookie by name no
longer has to remove every cookie with that name.
`browser_cookie_delete` (opt-in via `--caps=storage`) accepts optional
`domain` and `path` filters to leave other domains and paths untouched.
([microsoft/playwright#43319](https://redirect.github.com/microsoft/playwright/pull/43319))

#### 🐛 Fixes

- `fix(mcp): allow combining time, text and textGone in
browser_wait_for` — when combined with a text condition, `time` is its
timeout (capped at 30 seconds), not a delay before checking it.
Supplying both `text` and `textGone` now waits for the first condition
to happen, rather than both in sequence.
([microsoft/playwright#43011](https://redirect.github.com/microsoft/playwright/pull/43011))
- `fix(mcp): allow loopback hosts by default for all bind addresses` —
HTTP clients can connect through `localhost`, `127.0.0.1` or `[::1]`
regardless of the bind address. Other hosts still require
`--allowed-hosts`; binding to `0.0.0.0` prints a usable localhost URL.
([microsoft/playwright#42993](https://redirect.github.com/microsoft/playwright/pull/42993))
- `fix(mcp): pass credentials from --proxy-server as proxy
username/password` — credentials embedded in the proxy URL are now
passed to the browser as proxy authentication settings.
([microsoft/playwright#43071](https://redirect.github.com/microsoft/playwright/pull/43071))
- `fix(mcp): race browser_navigate_back against modal states` —
`browser_navigate_back` reports a dialog opened during history
navigation instead of timing out.
([microsoft/playwright#43252](https://redirect.github.com/microsoft/playwright/pull/43252))
- `fix(mcp): normalize bare host URLs and loopback IP addresses` —
`browser_navigate` handles scheme-less hosts with ports and uses HTTP
for loopback addresses such as `127.0.0.1:3000` and `[::1]:3000`.
([microsoft/playwright#43264](https://redirect.github.com/microsoft/playwright/pull/43264))
- `fix(mcp): do not close the browser twice when the client disconnects`
— stdio disconnects let the browser close gracefully instead of
force-killing it through a second close request. Dashboard annotation
processes also exit when their parent goes away.
([microsoft/playwright#43174](https://redirect.github.com/microsoft/playwright/pull/43174))
- `fix(mcp): give each isolated client its own idle timer` — with HTTP
transport and `--isolated`, an idle client's context now expires even
while another client keeps the shared browser busy.
([microsoft/playwright#43527](https://redirect.github.com/microsoft/playwright/pull/43527))
- `fix(mcp): apply route headers without bypassing origin filters` —
`browser_route` (opt-in via `--caps=network`) matches added request
header names case-insensitively, includes custom headers in mocked
responses, and preserves origin filters and other routes when modifying
request headers.
([microsoft/playwright#43227](https://redirect.github.com/microsoft/playwright/pull/43227),
[microsoft/playwright#43244](https://redirect.github.com/microsoft/playwright/pull/43244),
[microsoft/playwright#43637](https://redirect.github.com/microsoft/playwright/pull/43637))
- `fix(mcp): correct cookie filtering and missing-domain errors` —
`browser_cookie_list` (opt-in via `--caps=storage`) matches domain and
path boundaries instead of unrelated names such as `notexample.com` or
`/apiary`. `browser_cookie_set` asks for an explicit `domain` when the
current page has no hostname, such as `about:blank`.
([microsoft/playwright#43316](https://redirect.github.com/microsoft/playwright/pull/43316),
[microsoft/playwright#43368](https://redirect.github.com/microsoft/playwright/pull/43368),
[microsoft/playwright#43318](https://redirect.github.com/microsoft/playwright/pull/43318))
- `fix(mcp): accept Windows paths in browser_resume location` —
`browser_resume` (opt-in via `--caps=devtools`) no longer mistakes a
Windows drive-letter colon for the line-number separator.
([microsoft/playwright#43349](https://redirect.github.com/microsoft/playwright/pull/43349))
- `fix(mcp): report run-code route handler exceptions once and verbatim`
— `browser_run_code_unsafe` reports a route handler's thrown value
without duplicating it or wrapping non-Error values in another error.
([microsoft/playwright#43203](https://redirect.github.com/microsoft/playwright/pull/43203))
- `fix(extension): release debugger when attach completes after
connection close` — disconnecting while `browser_tabs` attaches to a new
tab no longer leaves that tab attached to the extension's debugger.
([microsoft/playwright#43025](https://redirect.github.com/microsoft/playwright/pull/43025))
- `fix(chromium): close pages that crashed before connecting over CDP` —
connecting through `--cdp-endpoint` no longer stalls on an already
crashed or discarded page; those pages are omitted from the tab list.
([microsoft/playwright#43075](https://redirect.github.com/microsoft/playwright/pull/43075))
- `fix(aria): skip text nodes that are not rendered` —
`browser_snapshot` and accessible names omit unrendered text, including
unslotted shadow-host text and text directly inside closed `<details>`.
([microsoft/playwright#43150](https://redirect.github.com/microsoft/playwright/pull/43150))
- `fix(a11y): treat inert elements and content outside of modal dialogs
as hidden` — snapshots exclude inert content and content outside the
topmost modal `<dialog>`. Click and fill actions wait for targets to
stop being inert instead of silently misfiring.
([microsoft/playwright#43211](https://redirect.github.com/microsoft/playwright/pull/43211))
- `fix(aria): do not count whitespace-only contributors as name sources`
— snapshots retain button names when whitespace around a hidden icon
previously caused the name to disappear.
([microsoft/playwright#43317](https://redirect.github.com/microsoft/playwright/pull/43317))
- `fix(aria): resolve label references consistently` — snapshots and
role locators recognize tab- or newline-separated label IDs and labels
assigned through `ariaLabelledByElements`, while retaining
attribute-based labels in older browsers.
([microsoft/playwright#43361](https://redirect.github.com/microsoft/playwright/pull/43361),
[microsoft/playwright#43577](https://redirect.github.com/microsoft/playwright/pull/43577),
[microsoft/playwright#43722](https://redirect.github.com/microsoft/playwright/pull/43722))
- `fix(aria): quote ~, .inf and .nan in aria snapshots` — YAML-like
names remain strings rather than being parsed as null or special
floating-point values.
([microsoft/playwright#43469](https://redirect.github.com/microsoft/playwright/pull/43469))
- `fix(aria): preserve iframe snapshots with fallback text` — snapshots
retain an iframe's contents when the iframe element also contains
fallback text.
([microsoft/playwright#43635](https://redirect.github.com/microsoft/playwright/pull/43635))
- `fix(aria): match mixed-case roles and states` — snapshots and role
locators recognize mixed-case `role` and ARIA state values, including
checked, pressed and expanded states.
([microsoft/playwright#43727](https://redirect.github.com/microsoft/playwright/pull/43727))

#### 📦 Upgrading

Configs that use `@playwright/mcp@latest` pick this release up on the
next client restart. To pin it:

```bash
npx @playwright/mcp@0.0.84
```

</details>

---

### Configuration

📅 **Schedule**: (UTC)

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♻ **Rebasing**: Whenever PR is behind base branch, or you tick the
rebase/retry checkbox.

🔕 **Ignore**: Close this PR and you won't be reminded about this update
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---

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View the [repository job
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Co-authored-by: renovate[bot] <29139614+renovate[bot]@users.noreply.github.com>
Co-authored-by: Paul Sorensen <paulnsorensen@gmail.com>
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Successfully merging this pull request may close these issues.

[MCP]: On stdin EOF the stdio server force-kills its own browser 1 ms after starting the graceful close (Windows)

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