[macOS Desktop 26.1007.30912] Recent sidebar shrinks to two after launch; active thread reads denied #53193

Environment

macOS 27.0.1 (26A434), desktop bundle version 26.1007.30912, build 20156. Installed bundle is ChatGPT.app. Local app-server reports 0.162.0-alpha.17.2; durable host reports 0.1.0. Observation: October 11, 2026, UTC.

Observed behavior

On launch, the user briefly sees all recent conversations, then only two. A just-used, active conversation disappears from the sidebar. Expected: accessible existing conversations remain discoverable, with an actionable unavailable state if metadata loading fails.

This is an existing-profile observation, not a clean-install or independently reproduced launch. No additional restart was performed during diagnosis because another task was actively controlling physical equipment.

Selected evidence

• Current launch log begins around 2026-10-11T19:20:57Z.
• At 2026-10-11T19:21:02.250Z, desktop method=thread/read for affected thread 01a108c1-9546-74df-8abe-d7ea26eab014 fails with error.code=-32003 and error.message="thread access denied".
• A read-only sample of the current launch log contained 326 Request failed rows with that error; this is a row count across threads, not unique request or thread count.
• All 17 sampled thread/list responses had errorCode=null.
• Around 19:23 UTC, supported list_threads returned 50 recent tasks plus one pinned conversation, with no unavailable hosts or sources. The affected thread appeared as active on host durable.
• Supported read_thread for the same affected ID succeeded and returned ongoing history. No conversation content is attached.
• Reported sidebar preferences: grouping=list on codex surface, chats sorted by updated_at. Actual visible filter and account/workspace selection were not inspected because the UI was in use.

Investigation request

Please compare desktop hydration authorization/access context and host routing with the successful supported direct read, and sidebar reconciliation after denied metadata reads. A launch-time access/context mismatch is a hypothesis, not a confirmed cause. No data loss, authorization bypass, or local database corruption is established. Please provide a supported recovery preserving active work and existing history.

Related reports

#51675, #52129, #51572, #53178 describe similar sidebar/direct-read or denied hydration behavior. Please consolidate if appropriate. This observation adds the brief-full-list-to-two launch sequence on version 26.1007.30912/build 20156 and a same-target successful direct read.

Privacy and interventions

Submitted by the AI assistant on the user's explicit instruction. Only selected diagnostic facts and the explicitly authorized affected thread ID are included. No raw logs, credentials, account identifiers, unrelated conversation content, screenshots, or local home paths are attached. No UI interaction, restart, sign-out, cache clearing, settings/database changes, or permissions/routing patches were performed.