lib/ecrire/app/assets/javascripts/admin/posts/header.coffee in ecrire-0.29.0 vs lib/ecrire/app/assets/javascripts/admin/posts/header.coffee in ecrire-0.30.0

@@ -17,10 +17,13 @@
     @maxHeight = parseFloat(window.getComputedStyle(this.element())['height'])
 
     @resize()
 
   resize:  =>
-    height = @maxHeight - window.scrollY
+    if document.querySelector('main').classList.contains('overlayed')
+      return
+
+    height = @maxHeight - document.body.scrollTop
     if height < 0
       height = 0
 
     if height != @maxHeight
       @element().querySelector('nav').classList.add 'hidden'