[BUG] Desktop app cannot rewind the first message.

Can't rewind to this message
ihave the same issue

Now at version Claude 1.5354.0 (9a9e3d) 2026-04-29T01:14:34.000Z , I can't even rewind to any messages. "Can't rewind to this message."

Replicable in Claude 1.6608.0 (f65729) 2026-05-07T14:16:09.000Z on Windows

Same issue here

same

Same issue here

Additional data: rewind breaks after thinking + tool_use turns, TUI unaffected

(written by Opus 4.7 after multiple debug sessions)

I've been hitting this consistently on Desktop v1.7196.0 (macOS, Claude Code 2.1.140) and did some digging that might help narrow it down.

What I'm seeing

Rewind works fine on simple text-only assistant responses. It breaks — on all messages in the session, including earlier ones — after the first assistant turn that produces both a thinking block and a tool_use block (e.g., asking it to draw a file tree).

Steps:

1. New Desktop session, send simple messages ("hi", "give me a hex code") — rewind works
2. Send something that triggers thinking + tool use ("draw a file tree of this project")
3. Rewind now shows "Can't rewind to this message" on every message, including the ones from step 1

The same sequence in the TUI works fine throughout.

What I found in the JSONL files

I compared the session files between Desktop and TUI. When an assistant response contains multiple content block types (thinking + tool_use), the streaming path writes them as separate JSONL entries — each with its own uuid but sharing the same API message.id, chained via parentUuid:

{ "uuid": "aaa", "parentUuid": "user_msg", "message": { "id": "msg_01TeyC...", "content": [{"type": "thinking"}] } }
{ "uuid": "bbb", "parentUuid": "aaa",      "message": { "id": "msg_01TeyC...", "content": [{"type": "tool_use"}] } }

Both Desktop and TUI produce this same split. The TUI handles it — I did 6+ successful rewinds in a session with 5 of these splits (including one message split across 4 entries). Desktop doesn't seem to cope with it.

I compared 3 sessions side by side:

| Surface | Entries | Split messages | Rewind |
|---------|---------|----------------|--------|
| Desktop | 28 | 1 | Fails after that turn |
| Desktop | 34 | 3 | Fails after first split turn |
| TUI | 102 | 5 (incl. a 4-way split) | Works throughout |

What I ruled out on my end

• Hooks: I have Stop hooks configured — disabled them entirely, reproduced the same issue in a fresh session
• Plugins: Same result with plugins enabled and disabled
• Model: All sessions on Sonnet 4.6, but this seems to trigger whenever thinking + tool_use co-occur regardless of model
• Session size: Happens on sessions as small as 28 entries

Speculation

It's possible Desktop's rewind logic expects a 1:1 mapping between assistant turns and JSONL entries, and the split breaks that assumption — but I don't have visibility into the validator code, so take that with a grain of salt. The key observation is that the TUI handles the exact same JSONL structure fine.

Happy to share the session JSONL files if they'd help with debugging.

Environment: Desktop v1.7196.0, Claude Code 2.1.140, macOS (Darwin 24.6.0)

See also #57206 (similar symptoms, different context) and #57819 (related to the streaming split architecture).

Confirmed: image attachments break rewind on Desktop.

I can reproduce this reliably on Desktop 1.7196.1 (macOS):

1. Start a new session, send a text-only message → rewind works ✓
2. Send a second message with an image attachment → "Can't rewind to this message" on all messages after that point

No tool_use involved — the assistant response to the image was pure text (no tools called). Thinking was enabled (showThinkingSummaries: true), but thinking is always present regardless of that setting.

This is a regression — rewind was working fine for me with the same setup (hooks, plugins, config) until a recent Desktop update.

Environment: Desktop 1.7196.1, Claude Code Opus 4.6 1M, macOS Darwin 24.6.0

Closing for now — inactive for too long. Please open a new issue if this is still relevant.

Yay :|