[Yury Semikhatsky (yury-s)]

Summary

• The handle path in UtilityScript.evaluate returned the page's thenable as is. Firefox and WebKit only await native promises, so a zone.js-style Promise wrapper came back unresolved from evaluateHandle and made waitForFunction resolve right away.
• Wrap a thenable result in a native promise on the handle path, same as the by-value path already does.

Fixes #43415

[github-actions]

Test results for "MCP"

2 failed
❌ [chromium] › mcp/webmcp-dynamic.spec.ts:189 › a tool registered in an iframe can be called after the page is reloaded @mcp-ubuntu-latest-chromium
❌ [msedge] › mcp/http.spec.ts:132 › http transport browser sigint @mcp-windows-latest-msedge

5152 passed, 614 skipped

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Merge workflow run.

[github-actions]

Test results for "tests 1"

3 flaky

⚠️ [chromium-library] › library/chromium/chromium.spec.ts:179 › serviceWorker(), and fromServiceWorker() work `@chromium-playwright-x64-ubuntu24-64-core-node22`
⚠️ [firefox-library] › library/browsercontext-cookies-third-party.spec.ts:257 › third party 'Partitioned;' cookies `@firefox-playwright-x64-ubuntu24-64-core-node22`
⚠️ [firefox-library] › library/browsercontext-cookies-third-party.spec.ts:470 › top level 'Partitioned;' cookie and same origin iframe `@firefox-playwright-x64-ubuntu24-64-core-node22`

23553 passed, 710 skipped

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Merge workflow run.

[github-actions]

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

🟢 Both failures are confirmed pre-existing flakes

At PR head 308b8a3, neither failure looks caused by this PR. The exact tests also fail on unrelated PRs and main-branch pushes, and both usually pass.

Details

Overall assessment

This PR changes thenable handling in UtilityScript.evaluate and adds coverage in page-evaluate.spec.ts. The two MCP failures have established cross-run flake histories on the same projects and CI bots.

Pre-existing flakes

• [chromium] › mcp/webmcp-dynamic.spec.ts:189 › a tool registered in an iframe can be called after the page is reloaded — on mcp-ubuntu-latest-chromium, this test passed 132 of 136 runs and failed 4. The failures include unrelated main-branch run 38469565272 at 7dcaa99 and PR run 38422676421 for chore: replace @babel/code-frame with own implementation #43337.
• [msedge] › mcp/http.spec.ts:132 › http transport browser sigint — on mcp-windows-latest-msedge, this test passed 129 of 134 runs and failed 5. The failures include unrelated main-branch run 38788336457 at b146af2 and PR run 38671600264 for chore(test runner): remove experimental esbuild transpilation #43411. This run timed out waiting for the browser-close log entry, matching its shutdown-race flake pattern.

_{Triaged by the Playwright bot - agent run}