diff --git a/static/aerbimJS.js b/static/aerbimJS.js
index f12f65f..df29684 100644
--- a/static/aerbimJS.js
+++ b/static/aerbimJS.js
@@ -602,9 +602,11 @@ function showContentPartTree (el) {
         $($arrow).css({rotate: '0deg'})
     }
     let scroll = $(window)[0].scrollY
-    $($(".left_curtain_documentation")[1]).find(".tree_documentation_container").css({height: 'fit-content'})
-    maxScroll = scroll + $(".documentation_block")[0].getBoundingClientRect().bottom - $(".left_curtain_documentation")[1].offsetHeight - 172
-    $($(".left_curtain_documentation")[1]).find(".tree_documentation_container").css({height: 'calc(100vh - 300px)'})
+    if ($(".left_curtain_documentation")[1]) {
+        $($(".left_curtain_documentation")[1]).find(".tree_documentation_container").css({height: 'fit-content'})
+        maxScroll = scroll + $(".documentation_block")[0].getBoundingClientRect().bottom - $(".left_curtain_documentation")[1].offsetHeight - 172
+        $($(".left_curtain_documentation")[1]).find(".tree_documentation_container").css({height: 'calc(100vh - 300px)'})
+    }
 }
 let waitingTop = null
 let maxScroll = null