Allow specifying icon on a dropdown button

wagtail/admin/templates/wagtailadmin/pages/listing/_button_with_dropdown.html

@@ -1,6 +1,6 @@
 {% load wagtailadmin_tags %}
 {% fragment as toggle_classname %}{{ classes|join:' ' }} {{ button_classes|join:' ' }}{% endfragment %}
 
-{% dropdown attrs=self.attrs toggle_icon="arrow-down" toggle_label=label toggle_aria_label=title toggle_classname=toggle_classname %}
+{% dropdown attrs=self.attrs toggle_icon=icon_name|default:"arrow-down" toggle_label=label toggle_aria_label=title toggle_classname=toggle_classname %}
     {% include "wagtailadmin/pages/listing/_dropdown_items.html" with buttons=buttons only %}
 {% enddropdown %}

wagtail/admin/wagtail_hooks.py

@@ -266,12 +266,12 @@ def page_listing_buttons(page, page_perms, next_url=None):
         )
 
     yield ButtonWithDropdownFromHook(
-        _("More"),
+        "",
         hook_name="register_page_listing_more_buttons",
         page=page,
         page_perms=page_perms,
         next_url=next_url,
-        classes={"button", "button-secondary", "button-small"},
+        icon_name="dots-horizontal",
         attrs={
             "target": "_blank",
             "rel": "noreferrer",

wagtail/admin/widgets/button.py

@@ -92,6 +92,7 @@ class BaseDropdownMenuButton(Button):
             "label": self.label,
             "title": self.attrs.get("title"),
             "classes": self.classes,
+            "icon_name": self.icon_name,
         }
 
     def render(self):