[BUG] Voice dictation: sent message contains the dictated text twice after typing a character and pressing Enter (macOS, Desktop Code tab)

Product: Claude desktop app (macOS), Code tab: the prompt box of a Claude Code session
App version: Claude 2.26454.2 · Claude Code 2.1.293
OS: macOS 26.6.2 (build 25G83)
Date and time: 9 October 2026, about 14:36 CEST

What happened

1. In the Code tab prompt box, I dictated a long message with the app's own microphone (dictation) button.
2. When the dictation finished, I typed one character by hand, a question mark, at the end of the dictated text.
3. I pressed Enter.
4. The message that was sent contained the dictated text twice: first the whole dictation with my «?», then a second copy of most of it (from a point near the start through to the end) appended after it, also ending with «?».

Expected

The message is sent once, exactly as it appeared in the box: the dictated text plus my «?».

Shape of the sent text

The sent message reads A + B + "?" + ", " + B + "?":

• A is the opening words of the dictation («The question is, for a given year»).
• B is the rest of the dictation (« that is 2026, um, I mean, I don't actually understand how the system works. … to that free application»).

So the segment after the first words was committed a second time. It looks as if a pending dictation segment was re-inserted when I typed into the box or pressed Enter, instead of being replaced.

Reproduction (as observed once; not yet retried)

• Dictate a multi-sentence message into the Code tab prompt box with the app's microphone button.
• Without clicking elsewhere, type a punctuation character at the end.
• Press Enter.

Notes

• It happened once. I don't know yet whether it happens every time.
• I can provide the exact sent text privately if useful.

Related

Possibly related to #79049 (dictation duplicating interim transcript segments, Windows, Chinese; closed as completed 20/07/2026). This one is on macOS, in English, on a later build, and the duplicate appeared after typing a character and pressing Enter.