Fix crash when joining empty rooms

Author: singiamtel

src/UI/components/single/Chat.tsx

@@ -57,7 +57,7 @@ export default function Chat(props: Readonly<HTMLAttributes<HTMLDivElement>>) {
             )}
             ref={ref}
         >
-            {messages[currentRoom.ID].map((message, index, arr) => (
+            {messages[currentRoom.ID] ? messages[currentRoom.ID].map((message, index, arr) => (
                 <ErrorBoundary
                     key={index}
                     fallbackRender={({ error: e }) => {
@@ -75,7 +75,7 @@ export default function Chat(props: Readonly<HTMLAttributes<HTMLDivElement>>) {
                         prev={arr[index - 1]}
                     />
                 </ErrorBoundary>
-            ))}
+            )) : null}
             <div className="relative h-0 w-0">
                 {/* invisible div to scroll to */}
                 <div

src/UI/components/single/TrainerCard/TrainerCard.tsx

@@ -111,6 +111,7 @@ export default function TrainerCard(
                                 src={user.avatar ?
                                     Sprites.getAvatar(user.avatar) :
                                     Sprites.getAvatar(167)}
+                                alt="avatar"
                                 className="w-20 h-20"
                             />
                         ) :
@@ -146,13 +147,13 @@ function UserCardButton({
     icon,
     onClick,
     disabled = false,
-}: {
+}: Readonly<{
     name: string;
     alt: string;
     icon: ReactNode;
     onClick: MouseEventHandler<HTMLButtonElement>;
     disabled?: boolean;
-}) {
+}>) {
     return (
         <button
             className={'text-sm rounded-lg px-4 py-2 flex-grow-0 border border-gray-700 flex flex-col justify-center items-center ' +