diff --git a/instances/templates/add_instance_volume.html b/instances/templates/add_instance_volume.html
index 4f8be1ab..aab3c130 100644
--- a/instances/templates/add_instance_volume.html
+++ b/instances/templates/add_instance_volume.html
@@ -69,7 +69,7 @@
                             <div class="col-sm-6">
                                 <label class="form-label" for="selected_storage">{% trans "Storage pool" %}</label>
                                 <select id="selected_storage" name="selected_storage" class="form-select" required
-                                        data-volumes-url="{% url 'volumes' instance.compute.id 'POOL' %}">
+                                        data-volumes-url="{% url 'volumes' instance.compute.id '__pool__' %}">
                                     <option value="" selected disabled>{% trans "Choose a pool" %}</option>
                                     {% for storage in storages_host %}
                                     <option value="{{ storage }}">{{ storage }}</option>
diff --git a/instances/templates/allinstances.html b/instances/templates/allinstances.html
index a3fe344b..ae62ccb2 100644
--- a/instances/templates/allinstances.html
+++ b/instances/templates/allinstances.html
@@ -120,58 +120,10 @@
     {% include "instances/vm_states_poll.html" %}
     <script src="{% static 'js/table_filter.js' %}"></script>
     <script src="{% static 'js/find_address.js' %}"></script>
+    {% if app_settings.VIEW_INSTANCES_LIST_STYLE == 'grouped' and request.user.is_superuser %}
+        <script src="{% static 'js/host_groups.js' %}"></script>
+    {% endif %}
     {% if request.user.is_superuser %}
-        <script>
-            // The new-VM dialog's CPU bars and capacity lines, read when the
-            // dialog opens, two reads at a time: a CPU read holds a worker for
-            // a second, a capacity read while it reads the host's VMs. Answers
-            // of an earlier opening are ignored.
-            const addInstance = document.getElementById("AddInstance");
-            let opening = 0, queue = [], reading = 0;
-
-            function setCpuUsage(cell, percent, text) {
-                const meter = cell.querySelector(".progress");
-                cell.querySelector(".progress-bar").style.width = (percent || 0) + "%";
-                if (percent === null) {
-                    meter.removeAttribute("aria-valuenow");
-                } else {
-                    meter.setAttribute("aria-valuenow", percent);
-                }
-                cell.querySelector(".cpu-usage-value").textContent = text;
-            }
-
-            // data: the answer, or null when the read failed
-            function show(element, data) {
-                if (element.classList.contains("compute-capacity")) {
-                    element.textContent = data === null ? "" : data.trim();
-                    return;
-                }
-                const usage = data !== null && typeof data.cpudata === "number" ? Math.round(data.cpudata) : null;
-                setCpuUsage(element, usage, usage === null ? "—" : usage + "%");
-            }
-
-            function readNext() {
-                while (reading < 2 && queue.length) {
-                    const element = queue.shift(), current = opening;
-                    reading++;
-                    $.get(element.dataset.url)
-                        .done((data) => { if (current === opening) show(element, data); })
-                        .fail(() => { if (current === opening) show(element, null); })
-                        .always(() => { reading--; readNext(); });
-                }
-            }
-
-            addInstance.addEventListener("show.bs.modal", function () {
-                opening++;
-                addInstance.querySelectorAll(".cpu-usage").forEach((cell) => setCpuUsage(cell, null, "…"));
-                // host by host, as the list shows them
-                queue = Array.from(addInstance.querySelectorAll(".cpu-usage, .compute-capacity"));
-                readNext();
-            });
-            addInstance.addEventListener("hide.bs.modal", function () {
-                opening++;
-                queue = [];
-            });
-        </script>
+        <script src="{% static 'js/new_vm_dialog.js' %}"></script>
     {% endif %}
 {% endblock script %}
diff --git a/instances/templates/allinstances_index_grouped.html b/instances/templates/allinstances_index_grouped.html
index cdfd118a..bbc60edf 100644
--- a/instances/templates/allinstances_index_grouped.html
+++ b/instances/templates/allinstances_index_grouped.html
@@ -5,7 +5,7 @@
         <thead>
             <tr>
                 <th scope="col" data-sort-method="none">
-                    <button type="button" class="btn btn-sm btn-link p-0" id="hide-all-instances" onclick="hide_all_host_instances()" aria-expanded="true"
+                    <button type="button" class="btn btn-sm btn-link p-0" id="hide-all-instances" aria-expanded="true"
                             aria-label="{% trans "Collapse or expand every host" %}">{% bs_icon 'arrows-collapse' %}</button>
                 </th>
                 <th scope="col">{% trans "Name" %}</th>
@@ -23,10 +23,10 @@
                 {% if compute.instance_set.count > 0 %}
                     <tr class="{% if compute.status is True %}table-secondary{% else %}table-warning{% endif %}" data-sort-method="none" data-group-header>
                         <td>
-                            <button type="button" class="btn btn-sm btn-link p-0" onclick="hide_host_instances('{{ compute.id }}')"
+                            <button type="button" class="btn btn-sm btn-link p-0 host-toggle"
                                     aria-expanded="true" aria-controls="host-vms-{{ compute.id }}"
                                     aria-label="{% blocktrans with name=compute.name %}Collapse or expand {{ name }}{% endblocktrans %}">
-                                <span id="collapse_host_instances_{{ compute.id }}" class="bi bi-chevron-up" aria-hidden="true"></span>
+                                <span class="host-chevron bi bi-chevron-up" aria-hidden="true"></span>
                             </button>
                         </td>
                         <td colspan="{% if app_settings.VM_DRBD_STATUS == 'True' %}3{% else %}2{% endif %}">
@@ -38,7 +38,7 @@
                                     <span class="badge bg-danger-subtle text-danger-emphasis">{% trans "Not connected" %}</span>
                                 {% endif %}
                                 <span class="small text-body-secondary">{% blocktrans count counter=compute.instance_set.count %}{{ counter }} VM{% plural %}{{ counter }} VMs{% endblocktrans %}</span>
-                                <span id="inst_count_badge_{{ compute.id }}" class="badge text-bg-secondary d-none">{% trans "collapsed" %}</span>
+                                <span class="host-collapsed-badge badge text-bg-secondary d-none">{% trans "collapsed" %}</span>
                             </div>
                         </td>
                         {% if compute.status is True %}
@@ -83,27 +83,3 @@
     </table>
 </div>
 
-{% block script %}
-<script>
-// a collapsed host's VM rows are hidden by its table body's class, so the
-// search (table_filter.js, the hidden attribute) can still hide them too
-function set_host_collapsed(tbody, collapsed) {
-    $(tbody).toggleClass('host-collapsed', collapsed);
-    $(tbody).find('[aria-controls]').attr('aria-expanded', !collapsed);
-    $(tbody).find('span[id^=collapse_host_instances_]').toggleClass('bi-chevron-down', collapsed).toggleClass('bi-chevron-up', !collapsed);
-    $(tbody).find('span[id^=inst_count_badge_]').toggleClass('d-none', !collapsed);
-    // expanded while any host is, as the next click collapses them all
-    $('#hide-all-instances').attr('aria-expanded', $('tbody.searchable').not('.host-collapsed').length > 0);
-}
-// every host the same way: collapsed, unless all already are
-function hide_all_host_instances() {
-    var bodies = $('tbody.searchable');
-    var collapse = bodies.not('.host-collapsed').length > 0;
-    bodies.each(function () { set_host_collapsed(this, collapse); });
-}
-function hide_host_instances(host) {
-    var tbody = $('#collapse_host_instances_' + host).closest('tbody');
-    set_host_collapsed(tbody, !tbody.hasClass('host-collapsed'));
-}
-</script>
-{% endblock %}
diff --git a/instances/templates/instance_actions.html b/instances/templates/instance_actions.html
index 0ad0031f..6b36c0d2 100644
--- a/instances/templates/instance_actions.html
+++ b/instances/templates/instance_actions.html
@@ -8,11 +8,11 @@
 <div class="d-flex justify-content-end">
 <div class="btn-group" role="group" aria-label="{% blocktrans with name=instance.name %}Actions for {{ name }}{% endblocktrans %}">
     <button class="btn btn-sm btn-outline-secondary" type="button" data-url="{% url 'console' instance.compute_id instance.uuid %}" data-window="console-{{ instance.uuid }}"
-        onclick="window.open(this.dataset.url, this.dataset.window, 'width=850,height=650')" aria-label="{% trans "Console" %}"{% if "console" not in actions %} disabled{% endif %}>{% bs_icon 'display' %} <span class="d-none d-sm-inline">{% trans "Console" %}</span></button>
+        aria-label="{% trans "Console" %}"{% if "console" not in actions %} disabled{% endif %}>{% bs_icon 'display' %} <span class="d-none d-sm-inline">{% trans "Console" %}</span></button>
     {% if "clone" in actions %}
         <a href="{% url 'instances:instance' instance.id %}#clone" class="btn btn-sm btn-outline-secondary" title="{% trans "Clone" %}" aria-label="{% trans "Clone" %}">{% bs_icon 'copy' %}</a>
     {% elif "poweron" in actions %}
-        <form action="{% url 'instances:poweron' instance.id %}" method="post" class="btn-group" onsubmit="showPleaseWaitDialog()">
+        <form action="{% url 'instances:poweron' instance.id %}" method="post" class="btn-group">
             {% csrf_token %}
             <button type="submit" class="btn btn-sm btn-outline-secondary" title="{% trans "Start" %}" aria-label="{% trans "Start" %}">{% bs_icon 'play-fill' %}</button>
         </form>
diff --git a/instances/templates/instances/settings_tab.html b/instances/templates/instances/settings_tab.html
index 2e581bf5..f749227d 100644
--- a/instances/templates/instances/settings_tab.html
+++ b/instances/templates/instances/settings_tab.html
@@ -770,7 +770,7 @@
                         <div class="col-12 col-sm">
                             <input class="form-control" id="clone_name" name="name" type="text" value="{{ instance.name }}-clone" aria-describedby="clone-name-help"
                                    data-source="{{ instance.name }}" data-guess-url="{% url 'instances:guess_clone_name' %}"
-                                   data-guess-mac-url="{% url 'instances:guess_mac_address' 'NAME' %}">
+                                   data-guess-mac-url="{% url 'instances:guess_mac_address' '__name__' %}">
                         </div>
                         <div class="col-12 col-sm-auto">
                             <button class="btn btn-secondary" type="button" id="guess-clone-name">{% trans "Guess" %}</button>
diff --git a/instances/tests/test_create_dialog_cpu.py b/instances/tests/test_create_dialog_cpu.py
index 54097ee7..4884e7f5 100644
--- a/instances/tests/test_create_dialog_cpu.py
+++ b/instances/tests/test_create_dialog_cpu.py
@@ -10,6 +10,7 @@ import unittest
 from unittest.mock import PropertyMock, patch
 
 from computes.models import Compute
+from django.conf import settings
 from django.contrib.auth import get_user_model
 from django.test import TestCase
 from django.urls import reverse
@@ -95,7 +96,8 @@ class CreateDialogCpuTestCase(TestCase):
     @unittest.skipUnless(shutil.which("node"), "node is not installed")
     def test_the_dialog_reads_host_by_host_two_at_a_time(self):
         page = self.page()
-        script = next(s for s in html.fromstring(page).xpath("//script[not(@src)]/text()") if "show.bs.modal" in s)
+        self.assertIn("/static/js/new_vm_dialog.js", html.fromstring(page).xpath("//script/@src"))
+        script = (settings.BASE_DIR / "static/js/new_vm_dialog.js").read_text()
         cpu = [reverse("compute_graph", args=[c.id]) for c in self.computes]
         line = [reverse("compute_capacity", args=[c.id]) for c in self.computes]
         js = RUN.replace("SCRIPT", json.dumps(script)).replace("CPU_URLS", json.dumps(cpu)).replace("LINE_URLS", json.dumps(line))
diff --git a/static/js/console_window.js b/static/js/console_window.js
new file mode 100644
index 00000000..430c22f8
--- /dev/null
+++ b/static/js/console_window.js
@@ -0,0 +1,6 @@
+// A console button (data-url, data-window) opens the console in one window
+// per VM: opening it again reloads that window.
+document.addEventListener("click", function (event) {
+    var button = event.target.closest("button[data-window]");
+    if (button) window.open(button.dataset.url, button.dataset.window, "width=850,height=650");
+});
diff --git a/static/js/host_groups.js b/static/js/host_groups.js
new file mode 100644
index 00000000..8d45daab
--- /dev/null
+++ b/static/js/host_groups.js
@@ -0,0 +1,24 @@
+// The VM list grouped by host (allinstances_index_grouped.html): a host's
+// VMs collapse under its row. A collapsed host's VM rows are hidden by its
+// table body's class, so the search (table_filter.js, the hidden attribute)
+// can still hide them too.
+function set_host_collapsed(tbody, collapsed) {
+    $(tbody).toggleClass('host-collapsed', collapsed);
+    $(tbody).find('[aria-controls]').attr('aria-expanded', !collapsed);
+    $(tbody).find('.host-chevron').toggleClass('bi-chevron-down', collapsed).toggleClass('bi-chevron-up', !collapsed);
+    $(tbody).find('.host-collapsed-badge').toggleClass('d-none', !collapsed);
+    // expanded while any host is, as the next click collapses them all
+    $('#hide-all-instances').attr('aria-expanded', $('tbody.searchable').not('.host-collapsed').length > 0);
+}
+
+// every host the same way: collapsed, unless all already are
+$('#hide-all-instances').on('click', function () {
+    var bodies = $('tbody.searchable');
+    var collapse = bodies.not('.host-collapsed').length > 0;
+    bodies.each(function () { set_host_collapsed(this, collapse); });
+});
+
+$('.host-toggle').on('click', function () {
+    var tbody = $(this).closest('tbody');
+    set_host_collapsed(tbody, !tbody.hasClass('host-collapsed'));
+});
diff --git a/static/js/instance_page.js b/static/js/instance_page.js
index f32d235e..1304d3af 100644
--- a/static/js/instance_page.js
+++ b/static/js/instance_page.js
@@ -50,10 +50,6 @@
         show_tab('#clone');
     });
 
-    // one window per VM: opening it again reloads it
-    on("console_button", "click", function () {
-        window.open(this.dataset.url, this.dataset.window, 'width=850,height=650');
-    });
     if (summary.dataset.vdiUrl) {
         $.get(summary.dataset.vdiUrl, function (data) {
             $("#vdi_url_input").attr("value", data);
@@ -88,7 +84,7 @@
     var pool = document.getElementById("selected_storage");
     if (pool) {
         pool.addEventListener("change", function () {
-            $.getJSON(pool.dataset.volumesUrl.replace("POOL", encodeURIComponent(pool.value)), function (data) {
+            $.getJSON(pool.dataset.volumesUrl.replace("__pool__", encodeURIComponent(pool.value)), function (data) {
                 var vols = $("#vols").empty();
                 $.each(data['vols'], function (i, item) {
                     vols.append($("<option>").val(item).text(item));
@@ -109,7 +105,7 @@
     var cloneName = document.getElementById("clone_name");
     // the DHCP host entry of the clone's name holds one address: the first NIC's
     function guess_mac_address() {
-        $.getJSON(cloneName.dataset.guessMacUrl.replace("NAME", encodeURIComponent(cloneName.value)), function (data) {
+        $.getJSON(cloneName.dataset.guessMacUrl.replace("__name__", encodeURIComponent(cloneName.value)), function (data) {
             $('input[name="clone-net-mac-0"]').val(data['mac']);
         });
     }
diff --git a/static/js/new_vm_dialog.js b/static/js/new_vm_dialog.js
new file mode 100644
index 00000000..c336438a
--- /dev/null
+++ b/static/js/new_vm_dialog.js
@@ -0,0 +1,50 @@
+// The new-VM dialog's CPU bars and capacity lines, read when the
+// dialog opens, two reads at a time: a CPU read holds a worker for
+// a second, a capacity read while it reads the host's VMs. Answers
+// of an earlier opening are ignored.
+const addInstance = document.getElementById("AddInstance");
+let opening = 0, queue = [], reading = 0;
+
+function setCpuUsage(cell, percent, text) {
+    const meter = cell.querySelector(".progress");
+    cell.querySelector(".progress-bar").style.width = (percent || 0) + "%";
+    if (percent === null) {
+        meter.removeAttribute("aria-valuenow");
+    } else {
+        meter.setAttribute("aria-valuenow", percent);
+    }
+    cell.querySelector(".cpu-usage-value").textContent = text;
+}
+
+// data: the answer, or null when the read failed
+function show(element, data) {
+    if (element.classList.contains("compute-capacity")) {
+        element.textContent = data === null ? "" : data.trim();
+        return;
+    }
+    const usage = data !== null && typeof data.cpudata === "number" ? Math.round(data.cpudata) : null;
+    setCpuUsage(element, usage, usage === null ? "—" : usage + "%");
+}
+
+function readNext() {
+    while (reading < 2 && queue.length) {
+        const element = queue.shift(), current = opening;
+        reading++;
+        $.get(element.dataset.url)
+            .done((data) => { if (current === opening) show(element, data); })
+            .fail(() => { if (current === opening) show(element, null); })
+            .always(() => { reading--; readNext(); });
+    }
+}
+
+addInstance.addEventListener("show.bs.modal", function () {
+    opening++;
+    addInstance.querySelectorAll(".cpu-usage").forEach((cell) => setCpuUsage(cell, null, "…"));
+    // host by host, as the list shows them
+    queue = Array.from(addInstance.querySelectorAll(".cpu-usage, .compute-capacity"));
+    readNext();
+});
+addInstance.addEventListener("hide.bs.modal", function () {
+    opening++;
+    queue = [];
+});
diff --git a/templates/base.html b/templates/base.html
index 105e16be..f1cedc85 100644
--- a/templates/base.html
+++ b/templates/base.html
@@ -85,6 +85,7 @@
     <script src="{% static 'js/sort_tables.js' %}"></script>
     <script src="{% static 'js/error_focus.js' %}"></script>
     <script src="{% static 'js/back_links.js' %}"></script>
+    <script src="{% static 'js/console_window.js' %}"></script>
     {% block script %}{% endblock %}
   </body>
 </html>