$("#setup-form").submit(() => { const username = $("#username").val(); const password1 = $("#password1").val(); const password2 = $("#password2").val(); if (!username) { showAlert("Username can't be empty"); return false; } if (!password1) { showAlert("Password can't be empty"); return false; } if (password1 !== password2) { showAlert("Both password fields need be identical."); return false; } server.post('setup', { username: username, password: password1 }).then(() => { window.location.replace("/"); }); return false; }); function showAlert(message) { $("#alert").html(message); $("#alert").show(); }