remove mention of core behavior

Author: jderochervlk

markdown-pages/docs/manual/array-and-list.mdx

@@ -52,10 +52,6 @@ var tenthItem = myArray[10];
 
 </CodeTab>
 
-The behavior of returning an `option` is new to V11 when you have [Core](/docs/manual/api/stdlib) open.
-It provides a safer way to access array items, which is especially useful when you're not sure if the index is out of bounds.
-If you would like to not use an `option`, you can use [`Array.getUnsafe`](/docs/manual/api/stdlib/array#value-getUnsafe).
-
 #### Update
 
 Items in an array can be updated by assigning a value to an index or using a function: