diff --git a/frontend/src/components/TopicDetail.vue b/frontend/src/components/TopicDetail.vue
index 37fb1f1..909418a 100644
--- a/frontend/src/components/TopicDetail.vue
+++ b/frontend/src/components/TopicDetail.vue
@@ -48,6 +48,7 @@ const inputEl = ref(null)
 
 function openChat() {
   chatOpen.value = true
+  nextTick(() => inputEl.value?.focus())
 }
 
 function closeChat() {