    ///   done on this offset.
    ///
    /// - Remark: The implementation of this violates the API contract of `ManagedBufferPointer` by
    ///   using its element pointer past the call to `withUnsafeMutablePointerToElements`. Based on
    ///   the implementation of `ManagedBufferPointer` this is safe to do so long as the buffer
    ///   itself lives past the usage of the pointer. In theory the stdlib could break this but that
    ///   seems rather unlikely as that would mean it would have to yield a pointer to temporary
    ///   storage, and that's contrary to the purpose of `ManagedBufferPointer`. This hack can be
    ///   removed if [SR-13876][] is fixed.
    ///
    /// [SR-13876]: https://bugs.swift.org/browse/SR-13876
    @inlinable
    subscript(_unsafeElementAt offset: Int) -> Element {
        _read {