How to get x number of random document in firestore with web v9

I’m working on a project where an explore page requires random posts. I want to get 10 random posts from the posts collection. I am using firebase web SDK v9.6.3.

This is code I have written to get x number of posts:

export async function getRandomPosts(postCount) {
   const q = query(
      collection(db, "posts"),
      limit(postCount)
      // orderBy("timestamp", "desc")
   );
   const querySnapshot = await getDocs(q);
   let posts = [];
   querySnapshot.forEach((doc) => {
      posts.push({
         id: doc.id,
         ...doc.data(),
         timestamp: doc.data().timestamp?.toDate().toString(),
      });
   });
   return posts;
}

I can’t find anything to get the random documents. Is there anything like rand in mySQL ?