Unexpected Supabase Auth Session Logout After 2–3 Seconds (email and OAuth)

export const supabase = createClient<Database>(
  import.meta.env.VITE_SUPABASE_URL,
  import.meta.env.VITE_SUPABASE_ANON_KEY,
  {
    auth: {
      autoRefreshToken: true,
      persistSession: true,
      detectSessionInUrl: true,
    },
  }
);

useEffect(() => {
  // handle SIGNED_IN, TOKEN_REFRESHED, SIGNED_OUT, INITIAL_SESSION events
  const { data: { subscription }} = supabase.auth.onAuthStateChange(
    (event, sessionData) => { … }
  );
  // initial session fetch
  const { data: { session: initialSession }} = await supabase.auth.getSession();
  // setSession, setUser, setInitialized…
}, [queryClient, isFirstTimeUser, handleWelcomeEmail]);