diff --git a/bookwyrm/templates/lists/list.html b/bookwyrm/templates/lists/list.html
index ab64fc9b6..509a67f63 100644
--- a/bookwyrm/templates/lists/list.html
+++ b/bookwyrm/templates/lists/list.html
@@ -92,7 +92,7 @@
                                         <summary>
                                             <span role="heading" aria-level="3">
                                                 {% trans "Edit notes" %}
-                                                <span class="details-close icon icon-pencil" aria-hidden></span>
+                                                <span class="details-close icon icon-pencil" aria-hidden="true"></span>
                                             </span>
                                         </summary>
                                         {% include "lists/edit_item_form.html" with book=item.book %}
@@ -107,7 +107,7 @@
                                 <summary>
                                     <span role="heading" aria-level="3">
                                         {% trans "Add notes" %}
-                                        <span class="details-close icon icon-plus" aria-hidden></span>
+                                        <span class="details-close icon icon-plus" aria-hidden="true"></span>
                                     </span>
                                 </summary>
                                 {% include "lists/edit_item_form.html" with book=item.book %}
diff --git a/bookwyrm/templates/search/book.html b/bookwyrm/templates/search/book.html
index cc615d508..7096a55de 100644
--- a/bookwyrm/templates/search/book.html
+++ b/bookwyrm/templates/search/book.html
@@ -45,7 +45,7 @@
                     <a href="{{ result_set.connector.base_url }}" target="_blank">{{ result_set.connector.name|default:result_set.connector.identifier }}</a>
                 </span>
 
-                <span class="details-close icon icon-x" aria-hidden></span>
+                <span class="details-close icon icon-x" aria-hidden="true"></span>
             </summary>
             {% endif %}
 
diff --git a/bookwyrm/templates/settings/link_domains/link_domains.html b/bookwyrm/templates/settings/link_domains/link_domains.html
index ceb0d8cb0..b633c5fbd 100644
--- a/bookwyrm/templates/settings/link_domains/link_domains.html
+++ b/bookwyrm/templates/settings/link_domains/link_domains.html
@@ -53,7 +53,7 @@
                         {% trans "View links" %}
                         ({{ domain.links.count }})
                     </span>
-                    <span class="details-close icon icon-x" aria-hidden></span>
+                    <span class="details-close icon icon-x" aria-hidden="true"></span>
                 </summary>
 
                 <div class="table-container mt-4">
diff --git a/bookwyrm/templates/settings/reports/report.html b/bookwyrm/templates/settings/reports/report.html
index a795273bc..3f83f0169 100644
--- a/bookwyrm/templates/settings/reports/report.html
+++ b/bookwyrm/templates/settings/reports/report.html
@@ -21,7 +21,7 @@
     <details class="details-panel box">
         <summary>
             <span class="title is-4">{% trans "Message reporter" %}</span>
-            <span class="details-close icon icon-x" aria-hidden></span>
+            <span class="details-close icon icon-x" aria-hidden="true"></span>
         </summary>
         <div class="box">
             {% trans "Update on your report:" as dm_template %}
diff --git a/bookwyrm/templates/snippets/filters_panel/filters_panel.html b/bookwyrm/templates/snippets/filters_panel/filters_panel.html
index c3ddeeeae..f0fe5d3f1 100644
--- a/bookwyrm/templates/snippets/filters_panel/filters_panel.html
+++ b/bookwyrm/templates/snippets/filters_panel/filters_panel.html
@@ -22,7 +22,7 @@
         </span>
         {% endif %}
 
-        <span class="details-close icon icon-x is-{{ size|default:'normal' }}" aria-hidden></span>
+        <span class="details-close icon icon-x is-{{ size|default:'normal' }}" aria-hidden="true"></span>
     </summary>
 
     <div class="mt-3">