fix(web): prevent Safari IME composition Enter from sending message

[micsama]

Fixes #1139

Problem

On Safari (macOS), pressing Enter to confirm CJK (Chinese/Japanese/Korean) IME input in the chat textarea sends the message immediately instead of just committing the composed text.

Root cause: Safari fires compositionend before keydown — the opposite of Chrome and Firefox. By the time the keydown handler runs, e.isComposing is already false, so the existing guard is bypassed.

Reference: WebKit bug 165004

Fix

Safari sets e.keyCode to 229 (VK_PROCESS) on every keydown event processed by the IME, including the confirmation Enter. This value is defined in the W3C UIEvents spec as the IME-processing sentinel and is never generated by a physical key on any keyboard layout.

- if (e.key === 'Enter' && !e.shiftKey && !e.isComposing) {
+ // keyCode 229 (VK_PROCESS) filters out IME-handled Enter on Safari, where
+ // compositionend fires before keydown leaving e.isComposing already false.
+ if (e.key === 'Enter' && !e.shiftKey && !e.isComposing && e.keyCode !== 229) {

Impact

• Safari + CJK IME: IME confirmation Enter no longer sends the message ✓
• Chrome / Firefox: e.isComposing already handles these correctly; keyCode !== 229 is a no-op ✓
• All keyboard layouts / locales: keyCode 229 is never produced by a physical key; no regression risk ✓

Test Plan

• macOS Safari — type with Chinese/Japanese/Korean input method, press Enter to confirm candidate → message should NOT send
• macOS Safari — press Enter normally (no IME active) → message should send
• Chrome / Firefox — same two cases above → behavior unchanged

[gemini-code-assist]

Summary of Changes

Hello, I'm Gemini Code Assist¹! I'm currently reviewing this pull request and will post my feedback shortly. In the meantime, here's a summary to help you and other reviewers quickly get up to speed!

This pull request resolves a browser-specific bug affecting Safari users who utilize CJK Input Method Editors (IMEs). It ensures that the 'Enter' key, when used to confirm IME composition, no longer prematurely sends a message, aligning Safari's behavior with other browsers like Chrome and Firefox. The fix specifically targets Safari's unique event firing order for compositionend and keydown events.

Highlights

• Safari IME Composition Fix: Addressed an issue in Safari where pressing Enter to confirm CJK (Chinese/Japanese/Korean) IME input in the chat textarea would immediately send the message instead of just committing the composed text.

Changelog

• src/channels/web/static/app.js
  • Modified the keydown event handler for the chat input to include an additional check for e.keyCode !== 229 to correctly handle IME confirmation on Safari.

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[gemini-code-assist]

Code Review

This pull request fixes a bug on Safari where confirming IME input with the Enter key incorrectly sends the chat message. The fix introduces a check for e.keyCode !== 229, which is a sentinel value used by Safari for IME-related key events. My review focuses on improving the maintainability of this workaround by suggesting the use of a named constant and enhancing the code comment with a reference to the underlying browser bug.

[gemini-code-assist]

Since keyCode is a deprecated property, it's helpful to include a permanent reference to the browser bug that necessitates this workaround. This provides valuable context for future maintainers and makes the comment more concise.

Suggested change

	// keyCode 229 (VK_PROCESS) filters out IME-handled Enter on Safari, where
	// compositionend fires before keydown leaving e.isComposing already false.
	// Filter out IME composition confirmation on Safari. `isComposing` is not reliable
	// as `compositionend` fires before `keydown`. See https://bugs.webkit.org/show_bug.cgi?id=165004

[gemini-code-assist]

To improve readability and maintainability, consider extracting the magic number 229 into a named constant like const VK_PROCESS = 229;. This could be defined at a suitable scope (e.g., at the top of the file). The comment already helpfully mentions VK_PROCESS, and using a constant would make the code even clearer.

[henrypark133]

Review: Safari IME Enter handling looks correct

This is a tight fix for the Safari composition ordering edge case, and the change stays contained to the existing keydown path.

Positives:

• The keyCode !== 229 guard directly targets the Safari IME-confirmation path without changing normal Enter behavior.
• The PR is small enough that the manual test plan is proportionate.
• Meaningful CI ran on the fork, so this is in a reasonable state to merge.

No blocking issues from my side.

[micsama]

Review: Safari IME Enter handling looks correct

This is a tight fix for the Safari composition ordering edge case, and the change stays contained to the existing keydown path.

Positives:

• The keyCode !== 229 guard directly targets the Safari IME-confirmation path without changing normal Enter behavior.
• The PR is small enough that the manual test plan is proportionate.
• Meaningful CI ran on the fork, so this is in a reasonable state to merge.

No blocking issues from my side.

Updated the comment per the bot's suggestion — added a reference to the WebKit bug (165004) and rephrased for clarity. Skipped the named constant since VK_PROCESS is only used once and the comment already explains it.

[zmanian]

Review: Safari IME composition Enter fix

Clean, minimal fix for a well-known Safari/WebKit bug. Adding e.keyCode !== 229 is the standard workaround.

• Safari fires compositionend before keydown, so e.isComposing is already false when Enter confirms CJK input
• keyCode 229 (VK_PROCESS) identifies IME-handled keystrokes regardless of composition state
• WebKit bug reference included: https://bugs.webkit.org/show_bug.cgi?id=165004
• 3 lines changed, no risk

Title check: accurate.

LGTM.