Fix contains proc to use a loop

code/__HELPERS/unsorted.dm

@@ -1232,10 +1232,10 @@ B --><-- A
 
 	return L
 
-/atom/proc/contains(var/atom/location)
-	if(!location)
-		return 0
-	if(location == src)
-		return 1
 
-	return contains(location.loc)
+/atom/proc/contains(var/atom/A)
+	if(!A)
+		return 0
+	for(var/atom/location = A.loc, location, location = location.loc); // Semicolon is for the empty statement.
+		if(location == src)
+			return 1

code/modules/tgui/states/deep_inventory.dm

@@ -1,7 +1,7 @@
  /**
   * tgui state: deep_inventory_state
   *
-  * Checks that the src_object is in the user's fist-level (backpack, webbing, etc) inventory.
+  * Checks that the src_object is in the user's deep (backpack, box, toolbox, etc) inventory.
  **/
 
 /var/global/datum/ui_state/deep_inventory_state/deep_inventory_state = new()

code/modules/tgui/states/notcontained.dm

@@ -15,7 +15,7 @@
 	return UI_CLOSE
 
 /mob/living/notcontained_can_use_topic(atom/src_object)
-	if(src in src_object.contents)
+	if(src_object.contains(src))
 		return UI_CLOSE // Close if we're inside it.
 	return default_can_use_topic(src_object)