[ChatGPT Desktop] Project chat cannot be re-pinned after unpinning; same chat pins normally on Web

What issue are you seeing?

In the ChatGPT Desktop app, an existing ordinary Chat inside a ChatGPT Project cannot be pinned again after it has been unpinned.

The Desktop app shows this toast:

You cannot pin a project or GPT conversation.

This is incorrect for the affected object: it is an ordinary project chat, not a Project object and not a custom GPT conversation.

The same exact chat can be pinned normally on chatgpt.com with no error. That isolates the failure to the Desktop surface rather than the chat's server-side pin eligibility.

Environment

• Surface with failure: ChatGPT Desktop app on macOS
• Mode: Chat
• Context: ChatGPT Project
• Plan: ChatGPT Pro 20x
• Observed: August 18, 2026
• Desktop build: 26.814.41407

Steps to reproduce

1. Have an ordinary Chat inside a ChatGPT Project that is already pinned.

2. Unpin that chat in ChatGPT Desktop.

3. In Desktop, open the chat's menu and choose Pin chat again.

4. Observe the toast:

   You cannot pin a project or GPT conversation.

5. Open the same exact chat on chatgpt.com.

6. Choose Pin chat.

7. The chat pins successfully on Web with no error.

Expected behavior

An eligible ordinary Chat inside a ChatGPT Project should be pinnable from Desktop, matching Web behavior and current OpenAI documentation.

Current Projects documentation states that users can pin a chat even when newer chats appear in the project:

https://learn.chatgpt.com/docs/projects

ChatGPT Release Notes also document pinning chats and projects from the sidebar:

https://help.openai.com/en/articles/6825453-chatgpt-release-notes

Actual behavior

• Web: same chat pins successfully.
• Desktop: same chat is rejected with You cannot pin a project or GPT conversation.
• The chat remains in the Project and otherwise works normally.

This looks like a Desktop-side object-type / pin-eligibility classification regression or stale client state. The exact internal cause is not proven.

In-product feedback and performance trace

The same reproduction was submitted through /feedback on August 18, 2026.

Feedback ID:

no-active-thread-01a015fb-db31-7171-b442-2aef5fb5607b

A performance trace was also uploaded for this reproduction.

Performance trace ID:

no-active-thread-01a01600-efa4-7d53-9e75-c5c0f92a704c

Related issue

• #38943 concerns ChatGPT Web pin state affecting Recents/sidebar rendering. It is related to pin/sidebar behavior but is not the same reproduction; this issue is specifically a Desktop-only failure to re-pin an otherwise eligible Project chat while Web succeeds.

Requested investigation

Please compare the Desktop and Web pin-eligibility/object-type checks for chats that belong to ChatGPT Projects, especially after an unpin → re-pin transition. Desktop should not classify an ordinary project chat as an ineligible Project/GPT conversation when the same server-side chat is accepted by Web.

No source files, tests, or entry points are named in the report. Start by locating the Desktop pin-action and eligibility checks, then compare the unpin-to-repin path for Project chats with the Web behavior; done means an ordinary Project chat can be re-pinned in Desktop without the Project/GPT error.