[App] Windows: bundled "sites" plugin can never install — "plugin `sites` was not found in marketplace `openai-bundled`" on every launch since 2026-09-10 (stuck at 0.1.66, marketplace declares 0.1.70)

Summary

On Windows, the bundled sites plugin fails to install on every single launch. The installed copy is pinned at 0.1.66 while the bundled marketplace declares 0.1.70, so the app decides it's missing, requests the install every start, and its own resolver rejects it:

warn [AppServerConnection] plugin_install_failed errorCategory=other
     errorMessage="plugin `sites` was not found in marketplace `openai-bundled`" errorName=Error

warn [BundledPluginsMarketplace] bundled_plugins_marketplace_install_failed
     bundledPluginSourcePath=./plugins/sites bundledPluginSourcePathKind=relative errorCategory=other

Net effect: Sites is permanently stuck at 0.1.66 and can never update.

The marketplace does contain it

%USERPROFILE%\.codex\.tmp\bundled-marketplaces\openai-bundled\.agents\plugins\marketplace.json:

{
  "name": "sites",
  "source": { "source": "local", "path": "./plugins/sites" },
  "policy": { "installation": "AVAILABLE", "authentication": "ON_INSTALL" },
  "category": "Productivity"
}

And ./plugins/sites/.codex-plugin/plugin.json reads "name": "sites", "version": "0.1.70".

Those files are byte-identical to the ones shipped inside the MSIX at app\resources\plugins\openai-bundled\plugins\sites. I also replaced the staged copy with a fresh copy taken straight from the package, and deleted .materialization-key to force a rebuild — same failure either way.

So the manifest points at it, the files are present and correct, and the installer still reports it isn't there.

Reproduces with no user configuration at all

I ran the app with ~/.codex entirely deleted — no config.toml, no marketplaces, no plugin list, nothing user-specific. The sites install failure still occurred (6 times in that single launch). It is not caused by user configuration.

That run also exposed what may be the underlying inconsistency. With no config, the staged marketplace was built with only 7 plugins, and sites was not among them:

bundled_plugins_marketplace_added marketplaceName=openai-bundled
  marketplacePluginNames=["codex-app-tools","browser","unified-computer-use",
                          "chrome","computer-use","latex","visualize"]

…and yet the app still requested the sites install. So the "which plugins to install" set (synced from the account — logs show hasExternalPluginStateSync=true) and the "what's in the marketplace" set (staged from the package) are produced independently and can disagree. When they disagree, this error is the result.

Worth noting: with my normal configuration the two lists do agree — sites is present in marketplacePluginNames — and the install still fails. So the list mismatch may not be the only problem.

Regression window

First appears 2026-09-10, the day before app 26.908.3777.0 was installed on this machine — so this is not caused by that build. The likeliest trigger is the 0.1.66 → 0.1.70 plugin version bump, which made the app begin attempting the install on every launch.

Not related to #44754

This machine also has a ~50% startup failure, reported separately as #44754. The two are independent: the sites failure occurs identically in launches that start successfully, several seconds after the UI is already up and usable.

A question, not a theory

sites is the only bundled plugin in the manifest carrying "authentication": "ON_INSTALL". I wonder whether "not found in marketplace" is a misleading error surfaced from a failure somewhere in the auth-on-install path — but I have no evidence for that, so I'm raising it only as something that might be worth checking.

Environment

• MSIX package: OpenAI.Codex 26.908.3777.0 (also occurred on the preceding build)
• App version reported internally: 26.908.31457
• Chromium: 152.0.7977.83
• Windows 11 Home 25H2, 10.0.26200.8894, x64
• Installed sites: 0.1.66 — marketplace declares 0.1.70

Logs: %LOCALAPPDATA%\Packages\OpenAI.Codex_2p2nqsd0c76g0\LocalCache\Local\Codex\Logs\

Happy to supply full logs or run any diagnostic that would help.

Start with the bundled marketplace staging and plugin-install resolver, using the logged bundled_plugins_marketplace_added event as the entry point. Compare %USERPROFILE%\.codex\.tmp\bundled-marketplaces\openai-bundled\.agents\plugins\marketplace.json with plugins/sites/.codex-plugin/plugin.json, then reproduce with ~/.codex deleted. Done means the bundled sites plugin upgrades from 0.1.66 to 0.1.70 without a repeated install failure on launch.