消除了两个空指针错误

client/ui/chat/ChatFragment.tsx

@@ -148,7 +148,7 @@ export default function ChatFragment({ target, showReturnButton, onReturnButtonC
 
         const oldest = messagesList[0]
         setMessagesList(returnMsgs.concat(messagesList))
-        setTimeout(() => chatPanelRef.current!.scrollTo({ top: $(`#chat_${target}_message_${oldest.id}`).get(0).offsetTop }), 200)
+        oldest && setTimeout(() => chatPanelRef.current!.scrollTo({ top: $(`#chat_${target}_message_${oldest.id}`).get(0).offsetTop }), 200)
     }
 
     React.useEffect(() => {

client/ui/custom-elements/chat-text.ts

@@ -22,6 +22,8 @@ customElements.define('chat-text', class extends HTMLElement {
         this.update()
     }
     update() {
+        if (this.span == null) return
+        
         this.span.textContent = this.textContent
         this.span.style.textDecoration = $(this).attr('underline') ? 'underline' : ''
         this.span.style.fontStyle = $(this).attr('em') ? 'italic' : ''