diff --git a/app/assets/stylesheets/application.css b/app/assets/stylesheets/application.css
index e67a6e3b2..0081293b3 100644
--- a/app/assets/stylesheets/application.css
+++ b/app/assets/stylesheets/application.css
@@ -1126,8 +1126,8 @@ div.attachments img { vertical-align: middle; }
 div.attachments span.author { font-size: 0.9em; color: #888; }
 
 div.thumbnails {margin:0.6em;}
-div.thumbnails div {background:#fff;border:2px solid #ddd;display:inline-block;margin-right:2px;}
-div.thumbnails img {margin: 3px; vertical-align: middle;}
+div.thumbnail {background:#fff;border:2px solid #ddd;display:inline-block;margin-right:2px;}
+div.thumbnail img {margin: 3px; vertical-align: middle;}
 #history div.thumbnails {margin-left: 2em;}
 
 p.other-formats { text-align: right; font-size:0.9em; color: #666; }
diff --git a/app/helpers/application_helper.rb b/app/helpers/application_helper.rb
index 3174261a9..50519c890 100644
--- a/app/helpers/application_helper.rb
+++ b/app/helpers/application_helper.rb
@@ -346,18 +346,18 @@ module ApplicationHelper
   def thumbnail_tag(attachment)
     thumbnail_size = Setting.thumbnails_size.to_i
     thumbnail_path = thumbnail_path(attachment, :size => thumbnail_size * 2)
-    link_to(
-      image_tag(
-        thumbnail_path,
-        :srcset => "#{thumbnail_path} 2x",
-        :style => "max-width: #{thumbnail_size}px; max-height: #{thumbnail_size}px;",
-        :title => attachment.filename,
-        :loading => "lazy"
-      ),
-      attachment_path(
-        attachment
+    tag.div class: 'thumbnail', title: attachment.filename do
+      link_to(
+        image_tag(
+          thumbnail_path,
+          :srcset => "#{thumbnail_path} 2x",
+          :style => "max-width: #{thumbnail_size}px; max-height: #{thumbnail_size}px;",
+          :alt => attachment.filename,
+          :loading => "lazy"
+        ),
+        attachment_path(attachment)
       )
-    )
+    end
   end
 
   def toggle_link(name, id, options={})
diff --git a/app/views/attachments/_links.html.erb b/app/views/attachments/_links.html.erb
index f098c1038..93cbddaea 100644
--- a/app/views/attachments/_links.html.erb
+++ b/app/views/attachments/_links.html.erb
@@ -42,7 +42,7 @@
   <% if images.any? %>
   <div class="thumbnails">
     <% images.each do |attachment| %>
-      <div><%= thumbnail_tag(attachment) %></div>
+      <%= thumbnail_tag(attachment) %>
     <% end %>
   </div>
   <% end %>
diff --git a/app/views/issues/tabs/_history.html.erb b/app/views/issues/tabs/_history.html.erb
index 8c6f6d31b..aa5795400 100644
--- a/app/views/issues/tabs/_history.html.erb
+++ b/app/views/issues/tabs/_history.html.erb
@@ -27,7 +27,7 @@
     <% if Setting.thumbnails_enabled? && (thumbnail_attachments = journal_thumbnail_attachments(journal)).any? %>
       <div class="thumbnails">
         <% thumbnail_attachments.each do |attachment| %>
-          <div><%= thumbnail_tag(attachment) %></div>
+          <%= thumbnail_tag(attachment) %>
         <% end %>
       </div>
     <% end %>
diff --git a/test/helpers/application_helper_test.rb b/test/helpers/application_helper_test.rb
index 31c87daea..573eda42b 100644
--- a/test/helpers/application_helper_test.rb
+++ b/test/helpers/application_helper_test.rb
@@ -1918,11 +1918,12 @@ class ApplicationHelperTest < Redmine::HelperTest
   end
 
   def test_thumbnail_tag
-    a = Attachment.find(3)
-    assert_select_in(
-      thumbnail_tag(a),
-      'a[href=?] img[title=?][src=?][loading="lazy"]',
-      "/attachments/3", "logo.gif", "/attachments/thumbnail/3/200")
+    attachment = Attachment.find(3)
+    assert_select_in thumbnail_tag(attachment), 'div.thumbnail[title=?]', 'logo.gif' do
+      assert_select 'a[href=?]', '/attachments/3' do
+        assert_select 'img[alt=?][src=?][loading="lazy"]', "logo.gif", "/attachments/thumbnail/3/200"
+      end
+    end
   end
 
   def test_link_to_project