#375 fix(recovery): race a second Facebook host in the reachability probe

[Anonymous]

Originally created by: kristofferR

After a network change (Wi-Fi switch, VPN, wake from sleep), WebKit keeps sending same-host requests down the dead pooled connection for about 44 seconds. Carrier's reachability probe, which decides when a stuck Messenger worker may reload, made one same-host request, so it reported Facebook unreachable for that whole window and recovery waited.

The probe now races its same-host HEAD /favicon.ico with a no-cors request to https://m.facebook.com/favicon.ico, which needs a fresh connection. Either answer proves reachability. The race is hand-written rather than Promise.any, which macOS 10.15's WebKit lacks; a test covers that.

Idea from fMess (MIT).

Ref [#360]

CodeRabbit reviews this change in the combined PR [#394].

[Anonymous]

Originally posted by: chatgpt-codex-connector[bot]

Codex Review Summary: ✅ Completed

This comment shows the latest Codex review activity on this pull request. | Review | Status | Commit | Review trigger | | --- | --- | --- | --- | | 📝 **Code Review** | ✅ **Completed** <relative-time datetime="2026-11-07T16:07:07.197762Z">2026-11-07T16:07:07.197762Z</relative-time> | `4b26505` | Manual request |

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[Anonymous]

Originally posted by: chatgpt-codex-connector[bot]

Codex Review: Didn't find any major issues. Delightful!

Reviewed commit: 4b265052b4

ℹ️ About Codex in GitHub

[Your team has set up Codex to review pull requests in this repo](https://chatgpt.com/codex/cloud/settings/general). Reviews are triggered when you - Open a pull request for review - Mark a draft as ready - Comment "@codex review". If Codex has suggestions, it will comment; otherwise it will react with 👍. Codex can also answer questions or update the PR. Try commenting "@codex address that feedback".

[Anonymous]

Originally posted by: kristofferR

⏸️ crq will not request further automated reviews for this pull request.

Reason: CodeRabbit reviews these changes once, in combined PR [#394]

Resume with crq unhold kristofferr/carrier 375.

[Anonymous]

Ticket changed by: kristofferR

• status: open --> closed

[Anonymous]

Originally posted by: kristofferR

✅ The administrative hold has been retired because this pull request merged. crq will not request further automated reviews.