Issue #2903831 by quicksketch, acbramley, Lendude, longwave, Mirroar, jibran:...

Issue #2903831 by quicksketch, acbramley, Lendude, longwave, Mirroar, jibran: Views attachments missing for some display machine names

(cherry picked from commit 456ea857)

core/modules/views/src/Plugin/views/display/DisplayPluginBase.php

@@ -363,9 +363,7 @@ public function useMoreText() {
    * {@inheritdoc}
    */
   public function acceptAttachments() {
-    // To be able to accept attachments this display have to be able to use
-    // attachments but at the same time, you cannot attach a display to itself.
-    if (!$this->usesAttachments() || ($this->definition['id'] == $this->view->current_display)) {
+    if (!$this->usesAttachments()) {
       return FALSE;
     }
 

core/modules/views/tests/modules/views_test_config/test_views/views.view.test_display_attachment.yml

@@ -56,10 +56,11 @@ display:
     position: 2
     display_options:
       displays:
-        page_1: page_1
-  page_1:
+        page: page
+        attachment_1: attachment_1
+  page:
     display_plugin: page
-    id: page_1
+    id: page
     display_title: Page
     position: 1
     display_options: