message: docs(changelog): 2.6.0-beta.0
diff: # Changelog
  +### [v2.6.0-beta.0](https://github.com/youzan/vant/compare/v2.5.9-beta.0...v2.6.0-beta.0)
  +
  +`2020-04-02`
  +
  +**Feature**
  +
  +- Form: add show-error prop [#5941](https://github.com/youzan/vant/issues/5941)
  +- Tabbar: add placeholder prop [#5979](https://github.com/youzan/vant/issues/5979)
  +- Sku: enable safe-area-inset-bottom by default [#5960](https://github.com/youzan/vant/issues/5960)
  +- Tabbar: enable safe-area-inset-bottom by default when fixed [#5968](https://github.com/youzan/vant/issues/5968)
  +- SubmitBar: enable safe-area-inset-bottom by default [#5956](https://github.com/youzan/vant/issues/5956)
  +- GoodsAction: enable safe-area-inset-bottom by default [#5955](https://github.com/youzan/vant/issues/5955)
  +- Swipe: allow swipe multiple item at once [#5953](https://github.com/youzan/vant/issues/5953)
  +
  +**Improvement**
  +
  +- NavBar: improve active feedback [#5949](https://github.com/youzan/vant/issues/5949)
  +- Popup: improve leave animation timing function [#5954](https://github.com/youzan/vant/issues/5954)
  +- Picker: improve scroll speed [#5951](https://github.com/youzan/vant/issues/5951)
  +
  +**Bug Fixes**
  +
  +- Button: icon-prefix prop not work [#5947](https://github.com/youzan/vant/issues/5947)
  +- Calendar: rendering error when activated [#5978](https://github.com/youzan/vant/issues/5978)
  +- Form: incorrect validation order when add field dynamically [b8dea3](https://github.com/youzan/vant/commit/b8dea3c13b7dbf6533169653c493a3156c07f1d4)
  +- NavBar: icon align center [#5948](https://github.com/youzan/vant/issues/5948)
  +- Stepper: readonly not work in lagacy mobile safari [#5976](https://github.com/youzan/vant/issues/5976)
  +
  ### [v2.5.9](https://github.com/youzan/vant/compare/v2.5.8...v2.5.9)
  `2020-03-31`
  