fix(core): Do not overwrite user provided conversation id in Vercel

[nicohrubec]

We set the conversation id unconditionally based on the resonse_id, so if a user calls Sentry.setConversationId() explicitly this will still be overwritten, which is unexpected.

Closes #19904 (added automatically)

[github-actions]

Semver Impact of This PR

🟢 Patch (bug fixes)

📋 Changelog Preview

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New Features ✨

Deps

• Bump mongodb-memory-server-global from 10.1.4 to 11.0.1 by dependabot in #19888
• Bump stacktrace-parser from 0.1.10 to 0.1.11 by dependabot in #19887

Bug Fixes 🐛

Core

• Do not overwrite user provided conversation id in Vercel by nicohrubec in #19903

• Return same value from startSpan as callback returns by s1gr1d in #19300

Other

• (cloudflare) Forward ctx argument to Workflow.do user callback by Lms24 in #19891
• (deps) Bump socket.io-parser to 4.2.6 to fix CVE-2026-33151 by chargome in #19880
• (nestjs) Add node to nest metadata by chargome in #19875
• (serverless) Add node to metadata by nicohrubec in #19878

Internal Changes 🔧

• (astro) Re-enable server island tracing e2e test in Astro 6 by Lms24 in #19872
• (lint) Resolve oxlint warnings by isaacs in #19893
• (node-integration-tests) Remove unnecessary file-type dependency by Lms24 in #19824

---

_{🤖 This preview updates automatically when you update the PR.}

[github-actions]

size-limit report 📦

⚠️ Warning: Base artifact is not the latest one, because the latest workflow run is not done yet. This may lead to incorrect results. Try to re-run all tests to get up to date results.

Path	Size	% Change	Change
@sentry/browser	25.69 kB	+0.2%	+49 B 🔺
@sentry/browser - with treeshaking flags	24.17 kB	+0.14%	+33 B 🔺
@sentry/browser (incl. Tracing)	42.67 kB	+0.13%	+54 B 🔺
@sentry/browser (incl. Tracing, Profiling)	47.33 kB	+0.12%	+55 B 🔺
@sentry/browser (incl. Tracing, Replay)	81.48 kB	+0.08%	+57 B 🔺
@sentry/browser (incl. Tracing, Replay) - with treeshaking flags	71.06 kB	+0.1%	+69 B 🔺
@sentry/browser (incl. Tracing, Replay with Canvas)	86.17 kB	+0.06%	+50 B 🔺
@sentry/browser (incl. Tracing, Replay, Feedback)	98.41 kB	+0.04%	+36 B 🔺
@sentry/browser (incl. Feedback)	42.48 kB	+0.08%	+30 B 🔺
@sentry/browser (incl. sendFeedback)	30.35 kB	+0.15%	+43 B 🔺
@sentry/browser (incl. FeedbackAsync)	35.4 kB	+0.12%	+39 B 🔺
@sentry/browser (incl. Metrics)	26.96 kB	+0.15%	+38 B 🔺
@sentry/browser (incl. Logs)	27.1 kB	+0.12%	+32 B 🔺
@sentry/browser (incl. Metrics & Logs)	27.78 kB	+0.15%	+39 B 🔺
@sentry/react	27.45 kB	+0.22%	+58 B 🔺
@sentry/react (incl. Tracing)	45.01 kB	+0.14%	+60 B 🔺
@sentry/vue	30.13 kB	+0.16%	+46 B 🔺
@sentry/vue (incl. Tracing)	44.52 kB	+0.09%	+39 B 🔺
@sentry/svelte	25.7 kB	+0.16%	+40 B 🔺
CDN Bundle	28.35 kB	+0.27%	+75 B 🔺
CDN Bundle (incl. Tracing)	43.57 kB	+0.15%	+62 B 🔺
CDN Bundle (incl. Logs, Metrics)	29.22 kB	+0.27%	+77 B 🔺
CDN Bundle (incl. Tracing, Logs, Metrics)	44.43 kB	+0.17%	+75 B 🔺
CDN Bundle (incl. Replay, Logs, Metrics)	68.29 kB	+0.13%	+85 B 🔺
CDN Bundle (incl. Tracing, Replay)	80.41 kB	+0.1%	+73 B 🔺
CDN Bundle (incl. Tracing, Replay, Logs, Metrics)	81.31 kB	+0.1%	+76 B 🔺
CDN Bundle (incl. Tracing, Replay, Feedback)	85.97 kB	+0.12%	+103 B 🔺
CDN Bundle (incl. Tracing, Replay, Feedback, Logs, Metrics)	86.86 kB	+0.1%	+86 B 🔺
CDN Bundle - uncompressed	82.7 kB	+0.1%	+77 B 🔺
CDN Bundle (incl. Tracing) - uncompressed	128.62 kB	+0.05%	+64 B 🔺
CDN Bundle (incl. Logs, Metrics) - uncompressed	85.57 kB	+0.1%	+77 B 🔺
CDN Bundle (incl. Tracing, Logs, Metrics) - uncompressed	131.49 kB	+0.05%	+64 B 🔺
CDN Bundle (incl. Replay, Logs, Metrics) - uncompressed	209.22 kB	+0.05%	+102 B 🔺
CDN Bundle (incl. Tracing, Replay) - uncompressed	245.5 kB	+0.04%	+89 B 🔺
CDN Bundle (incl. Tracing, Replay, Logs, Metrics) - uncompressed	248.35 kB	+0.04%	+89 B 🔺
CDN Bundle (incl. Tracing, Replay, Feedback) - uncompressed	258.41 kB	+0.04%	+89 B 🔺
CDN Bundle (incl. Tracing, Replay, Feedback, Logs, Metrics) - uncompressed	261.26 kB	+0.04%	+89 B 🔺
@sentry/nextjs (client)	47.4 kB	+0.08%	+37 B 🔺
@sentry/sveltekit (client)	43.12 kB	+0.12%	+51 B 🔺
@sentry/node-core	56.42 kB	+0.13%	+73 B 🔺
@sentry/node	173.38 kB	+0.13%	+221 B 🔺
@sentry/node - without tracing	96.43 kB	+0.1%	+87 B 🔺
@sentry/aws-serverless	113.44 kB	+0.09%	+100 B 🔺

View base workflow run

[github-actions]

node-overhead report 🧳

Note: This is a synthetic benchmark with a minimal express app and does not necessarily reflect the real-world performance impact in an application.
⚠️ Warning: Base artifact is not the latest one, because the latest workflow run is not done yet. This may lead to incorrect results. Try to re-run all tests to get up to date results.

Scenario	Requests/s	% of Baseline	Prev. Requests/s	Change %
GET Baseline	8,622	-	9,006	-4%
GET With Sentry	1,646	19%	1,671	-1%
GET With Sentry (error only)	6,062	70%	6,054	+0%
POST Baseline	1,210	-	1,177	+3%
POST With Sentry	583	48%	577	+1%
POST With Sentry (error only)	1,050	87%	1,018	+3%
MYSQL Baseline	3,212	-	3,139	+2%
MYSQL With Sentry	413	13%	459	-10%
MYSQL With Sentry (error only)	2,620	82%	2,578	+2%

View base workflow run

[Lms24]

The change LGTM but I agree with bugbot that we should harden the test.

L: Not sure if this is a me-Problem but I had a hard time understanding the PR title. IIUC this fix ensures we don't overwrite a user-provided (custom) conversationId. Maybe we can change the title to something like "do not overwrite user-provided conversation id"? Just a suggestion, feel free to disregard

[chargome]

The change itself looks fine to me, but improving the test sounds good 👍

[cursor]

Cursor Bugbot has reviewed your changes and found 1 potential issue.

^{Bugbot Autofix is OFF. To automatically fix reported issues with cloud agents, enable autofix in the Cursor dashboard.}

[nicohrubec]

@Lms24 thanks for the suggestions I updated the test to be more strict and I agree that your proposed PR title should be a bit more clear so I changed it as well