[Bug]: Textarea submits input on Enter key during IME composition

[dennykuo]

Platform

macOS

Operating system version

26.2（25C56）

System architecture

ARM64 (M1, M2, etc)

PolyScope Version

0.13.0

Bug description

When typing in the textarea using an IME (Input Method Editor), pressing the Enter key to confirm a candidate selection unexpectedly triggers form submission instead of only completing the character composition.
Steps to Reproduce:

Focus on the textarea input field.
Switch to an IME-based input method (e.g., Traditional Chinese, Japanese, Korean, or any other language that requires an IME for character composition).
Type a sequence that opens the candidate list.
Press Enter to select a candidate.

Expected Behavior:
Pressing Enter during an active IME composition session should only confirm the selected candidate character. The textarea should not submit or send the input content at this point.

Actual Behavior:
Pressing Enter both confirms the candidate selection and simultaneously triggers submission of the input, even though the user has not finished composing their message.

Suggested Fix:
Check the isComposing property of the KeyboardEvent, or listen for compositionstart / compositionend events to distinguish between IME composition input and regular key presses. During an active composition session, the Enter key event should be suppressed from triggering submission.

Steps to reproduce

No response

Relevant log output

[mpociot]

This is now fixed in 0.14.0

[dennykuo]

Thanks for the fix in 0.14.0. Unfortunately, the issue persists on my end.

Environment:

• macOS 26.2 (25C56)
• Apple Silicon (M-series)
• PolyScope 0.14.0
• Input method: Traditional Chinese Zhuyin (Bopomofo)

Reproduction:

1. Focus on the textarea.
2. Switch to an IME input method.
3. Type a phonetic sequence that opens the candidate list.
4. Press Enter to confirm candidate selection.

Result: Enter still both confirms the candidate and submits the message simultaneously.

It's possible the fix is checking event.isComposing on the keydown event but not on keyup, or the composition state flag is being reset before the Enter key handler runs. A common pattern that works reliably across browsers:

let isComposing = false;

textarea.addEventListener('compositionstart', () => { isComposing = true; });
textarea.addEventListener('compositionend', () => { isComposing = false; });
textarea.addEventListener('keydown', (e) => {
  if (e.key === 'Enter' && !e.shiftKey && !isComposing && !e.isComposing) {
    e.preventDefault();
    submit();
  }
});

Note: relying solely on e.isComposing can be unreliable in some browsers/frameworks — maintaining a manual flag via compositionstart/compositionend is more robust.

Let me know if you need any further details or logs to debug this.

[dennykuo]

Confirmed working in 0.15.0. By the way, Polyscope is the best agent collaboration tool I've used so far. Great work!