3.**[Adding new auth client support](https://github.com/yiisoft/yii2/issues/1652)**
For better maintenability, we will not add any additional auth clients to the core extension. They should be done
in terms of user extensions.
4.**When using closures** it is recommended to **include all passed parameters** in the signature even if not all of them are
used. This way modifying or copying code is easier because all information is directly visible and it is not necessary to
look up which params are actually available in the documentation. ([#6584](https://github.com/yiisoft/yii2/pull/6584), [#6875](https://github.com/yiisoft/yii2/issues/6875))
