*   Fixed usage of optional scopes in URL helpers.

    *Alex Robbin*

*   Fixed handling of positional url helper arguments when `format: false`. 

    Fixes #17819.

    *Andrew White*, *Tatiana Soukiassian*

Please check [4-2-stable](https://github.com/rails/rails/blob/4-2-stable/actionpack/CHANGELOG.md) for previous changes.