diff --git a/src/channels/web/static/app.js b/src/channels/web/static/app.js
index 081b0f3a..ceab682a 100644
--- a/src/channels/web/static/app.js
+++ b/src/channels/web/static/app.js
@@ -1759,7 +1759,10 @@ chatInput.addEventListener('keydown', (e) => {
     }
   }
 
-  if (e.key === 'Enter' && !e.shiftKey && !e.isComposing) {
+  // Safari fires compositionend before keydown, so e.isComposing is already false
+  // when Enter confirms IME input. keyCode 229 (VK_PROCESS) catches this case.
+  // See https://bugs.webkit.org/show_bug.cgi?id=165004
+  if (e.key === 'Enter' && !e.shiftKey && !e.isComposing && e.keyCode !== 229) {
     e.preventDefault();
     hideSlashAutocomplete();
     sendMessage();