diff --git a/apps/common/main/lib/util/desktopinit.js b/apps/common/main/lib/util/desktopinit.js
index 9cd5677cd2..8a7680746b 100644
--- a/apps/common/main/lib/util/desktopinit.js
+++ b/apps/common/main/lib/util/desktopinit.js
@@ -55,6 +55,12 @@ if ( window.AscDesktopEditor ) {
                 type: theme.type,
             }
 
+            if ( /dark|light/.test(theme.system) ) {
+                window.uitheme.is_system_theme_dark = function () {
+                    return theme.system == 'dark';
+                }
+            }
+
             if ( map_themes && map_themes[theme.id] ) {
                 window.uitheme.colors = map_themes[theme.id].colors;
                 // window.desktop.themes = map_themes;