GitHub option greyed out in Project knowledge despite connected GitHub account

Screenshot

<img width="702" height="340" alt="Image" src="https://github.com/user-attachments/assets/554eea54-edcb-4d50-b683-e64756caf151" />

What were you trying to do?

In a Project's knowledge section, the "GitHub" option in the "+" menu is greyed out, so I can't sync a repository into the Project. "Upload from device" and "Add text content" work as normal.

What happened instead?

What I've checked:

Settings → Connectors → GitHub Integration shows "GitHub account connected".
"Check repository status" for the target repo is green ("Claude Code cloud sessions can work in <repo>").
The Claude GitHub App shows as not installed, but the repository check passes.
The option is greyed out both in the Claude desktop app and on claude.ai in the browser, including after reloading the page.

Setup:

Organization account on a Team plan
The Project is shared with the whole organization
Target repository is private and belongs to a GitHub organization

Expected: I can select GitHub and add files from the repository to the Project knowledge.
Actual: The GitHub option is disabled and can't be clicked, and no reason is shown.

Is this caused by an organization setting, a Project permission or sharing setting, or a missing GitHub App installation, and how can it be enabled?

Diagnostics

Filed from: GitHub settings for Claude Code on claude.ai
Report code: GH-388933
Page: claude.ai/customize/connectors/integration-github
Client: desktop