Eliminate jQuery usage in the login page

static/js/signup.js

@@ -1,8 +1,9 @@
-$(function () {
+window.addEventListener("DOMContentLoaded", function(e) {
+    var email = document.getElementById("signup-email");
+    var submitBtn = document.getElementById("signup-go");
 
     function submitForm() {
-        var base = document.getElementById("base-url").getAttribute("href").slice(0, -1);
-        var email = $("#signup-email").val();
+        submitBtn.disabled = true;
 
         try {
             var tz = Intl.DateTimeFormat().resolvedOptions().timeZone;
@@ -10,30 +11,33 @@ $(function () {
             var tz = "UTC";
         }
 
-        $("#signup-go").prop("disabled", true);
-        $.ajax({
-            url: base + "/accounts/signup/",
-            type: "post",
-            data: {"identity": email, "tz": tz},
-            success: function(data) {
-                $("#signup-result").html(data).show();
-                $("#signup-go").prop("disabled", false);
-            }
-        });
+        var payload = new FormData();
+        payload.append("identity", email.value);
+        payload.append("tz", tz);
+
+        var base = document.getElementById("base-url").getAttribute("href").slice(0, -1);
+        fetch(base + "/accounts/signup/", {method: "POST", body: payload})
+            .then(response => response.text())
+            .then(function(text) {
+                var resultLine = document.getElementById("signup-result");
+                resultLine.innerHTML = text;
+                resultLine.style.display = "block";
+                submitBtn.disabled = false;
+            });
 
         return false;
     }
 
-    $("#signup-go").on("click", submitForm);
-
-    $("#signup-email").keypress(function (e) {
+    // Wire up the submit button and the Enter key
+    submitBtn.addEventListener("click", submitForm);
+    email.addEventListener("keyup", function(e) {
         if (e.which == 13) {
             return submitForm();
         }
     });
 
-    $("#signup-modal").on('shown.bs.modal', function () {
-        $("#signup-email").focus()
-    })
-
-});
+    var modal = document.getElementById("signup-modal");
+    modal.addEventListener("shown.bs.modal", function() {
+        email.focus();
+    });
+});

templates/accounts/login.html

@@ -152,8 +152,7 @@
 
 {% block scripts %}
 {% compress js %}
-<script src="{% static 'js/jquery-3.6.0.min.js' %}"></script>
-<script src="{% static 'js/bootstrap.min.js' %}"></script>
+<script src="{% static 'js/bootstrap-native.min.js' %}"></script>
 <script src="{% static 'js/signup.js' %}"></script>
 {% endcompress %}
 {% endblock %}