Subscript expressions do not have to evaluate to integers

The following documentation comment has been logged on the website:

Page: https://www.postgresql.org/docs/12/sql-expressions.html
Description:

Section 4.2.3. Subscripts of the documentation states:

> Each subscript is itself an expression, which must yield an integer
value.

However, the following query works on Postgres 12.1

SELECT (ARRAY[1, 2, 3]::integer[])[1.5];

 array
-------
     2

I believe a more appropriate statement would acknowledge that at least some
values undergo an explicit-style conversion to an integer.