diff --git a/lib/cooked_post_processor.rb b/lib/cooked_post_processor.rb
index f0e3537ebf6..ffeffe788e0 100644
--- a/lib/cooked_post_processor.rb
+++ b/lib/cooked_post_processor.rb
@@ -415,7 +415,10 @@ class CookedPostProcessor
 
     %w{src data-small-upload}.each do |selector|
       @doc.css("img[#{selector}]").each do |img|
-        img[selector] = UrlHelper.cook_url(img[selector].to_s, secure: @post.with_secure_media?)
+        custom_emoji = img["class"]&.include?("emoji-custom") && Emoji.custom?(img["title"])
+        img[selector] = UrlHelper.cook_url(
+          img[selector].to_s, secure: @post.with_secure_media? && !custom_emoji
+        )
       end
     end
   end
diff --git a/spec/components/cooked_post_processor_spec.rb b/spec/components/cooked_post_processor_spec.rb
index 809b63555ac..9de2d5b6287 100644
--- a/spec/components/cooked_post_processor_spec.rb
+++ b/spec/components/cooked_post_processor_spec.rb
@@ -1359,6 +1359,26 @@ describe CookedPostProcessor do
           HTML
         end
 
+        it "doesn't use the secure media URL for custom emoji" do
+          CustomEmoji.create!(name: 'trout', upload: upload)
+          Emoji.clear_cache
+          Emoji.load_custom
+          stored_path = Discourse.store.get_path_for_upload(upload)
+          upload.update_column(:url, "#{SiteSetting.Upload.absolute_base_url}/#{stored_path}")
+          upload.update_column(:secure, true)
+
+          the_post = Fabricate(:post, raw: "This post has a custom emoji :trout:")
+          the_post.cook(the_post.raw)
+
+          cpp = CookedPostProcessor.new(the_post)
+          cpp.optimize_urls
+
+          upload_url = upload.url.gsub(SiteSetting.Upload.absolute_base_url, "https://s3.cdn.com")
+          expect(cpp.html).to match_html <<~HTML
+            <p>This post has a custom emoji <img src="#{upload_url}?v=#{Emoji::EMOJI_VERSION}" title=":trout:" class="emoji emoji-custom" alt=":trout:" loading="lazy" width="20" height="20"></p>
+          HTML
+        end
+
         context "media uploads" do
           fab!(:image_upload) { Fabricate(:upload) }
           fab!(:audio_upload) { Fabricate(:upload, extension: "ogg") }