diff --git a/core/modules/system/css/components/ajax-progress.module.css b/core/modules/system/css/components/ajax-progress.module.css
index 240cf7d686..c051c4b834 100644
--- a/core/modules/system/css/components/ajax-progress.module.css
+++ b/core/modules/system/css/components/ajax-progress.module.css
@@ -29,7 +29,7 @@ tr .ajax-progress-throbber .throbber {
 /* Full screen throbber */
 .ajax-progress-fullscreen {
   position: fixed;
-  z-index: 1000;
+  z-index: 1500;
   top: 48.5%;
   /* Can't do center:50% middle: 50%, so approximate it for a typical window size. */
   left: 49%; /* LTR */
diff --git a/core/themes/claro/css/components/ajax-progress.module.css b/core/themes/claro/css/components/ajax-progress.module.css
index ef71b0340e..9dc691bc7a 100644
--- a/core/themes/claro/css/components/ajax-progress.module.css
+++ b/core/themes/claro/css/components/ajax-progress.module.css
@@ -95,7 +95,7 @@
 .ajax-progress--fullscreen,
 .ui-dialog .ajax-progress--throbber {
   position: fixed;
-  z-index: 1000;
+  z-index: 1500;
   top: 50%;
   left: 50%;
   box-sizing: border-box;
diff --git a/core/themes/claro/css/components/ajax-progress.module.pcss.css b/core/themes/claro/css/components/ajax-progress.module.pcss.css
index 5047f3f220..8819aabe94 100644
--- a/core/themes/claro/css/components/ajax-progress.module.pcss.css
+++ b/core/themes/claro/css/components/ajax-progress.module.pcss.css
@@ -82,7 +82,7 @@
 .ajax-progress--fullscreen,
 .ui-dialog .ajax-progress--throbber {
   position: fixed;
-  z-index: 1000;
+  z-index: 1500;
   top: 50%;
   left: 50%;
   box-sizing: border-box;
diff --git a/core/themes/stable/css/system/components/ajax-progress.module.css b/core/themes/stable/css/system/components/ajax-progress.module.css
index de9efd41fb..5fafd52908 100644
--- a/core/themes/stable/css/system/components/ajax-progress.module.css
+++ b/core/themes/stable/css/system/components/ajax-progress.module.css
@@ -29,7 +29,7 @@ tr .ajax-progress-throbber .throbber {
 /* Full screen throbber */
 .ajax-progress-fullscreen {
   position: fixed;
-  z-index: 1000;
+  z-index: 1500;
   top: 48.5%;
   /* Can't do center:50% middle: 50%, so approximate it for a typical window size. */
   left: 49%; /* LTR */