Good catch, that's indeed the case.

However, the original version still has an issue if `id_` is False, since it will mark anything passed as `content` safe.

I see two ways to fix this:

1) We can either apply `conditional_escape` to `contents` after this line, but the double-escaping of lazy strings would kick in (#20221).

2) Another option would be to add an `else` clause to the `if id_:` clause and apply `conditional_escape` there.