[bugfix] Fix the error: Uncaught TypeError: Cannot read properties of null (reading 'scrollTop')

I just put Early return, though.

src-ui/app/main_page/main_section/message_container/log_box/LogBox.jsx

@@ -21,6 +21,7 @@ export const LogBox = () => {
     useEffect(() => {
         const handleScroll = () => {
             const element = log_container_ref.current;
+            if (!element) return;
             const currentScrollTop = element.scrollTop;
             const at_bottom = element.scrollHeight - currentScrollTop === element.clientHeight;