• Update postcss-font-family-system-ui to version 3.0
  by @JLHwung in #443
• Update postcss-cli usage example in docs
  by @RyanZim in #444

• Fixed: remove incorrect "postinstall" npm script
  (#404 - @MoOx)

• Fixed: specify the actual require peer dependency for caniuse database (caniuse-lite is used since latest caniuse-api latest major bump)
  (@MoOx)
• Fixed: bump dependencies not updated to PostCSS@6
  (#401 - @MoOx)

Removed: support for node 0.12

Node 4+ is supported.

Changed: upgrade to PostCSS 6

All postcss plugins dependencies have been updated to latest version to ensure
full PostCSS 6 compatibility.

Some breaking (minor) changes:

• image-set polyfill change 2x from 144dpi to 192dpi
• whitespace changes for image-set polyfill output
• rebeccapurpule is now an hexa number
• custom-selector does not output useless (empty) blocks with a selector with no rules associated

You can expect some other since all postcss plugins used have been updated to
latest versions.
If you have unexpected regression, please check corresponding plugins changelog before opening an issue.

Added: warning is emitted is you use custom property sets and @apply

This feature won't be included in next the major release of postcss-cssnext.

This most likely won't get any more support from browser vendors as the
spec is yet considered deprecated and alternative solutions are being
discussed.
Read more about the reason here https://github.com/pascalduez/postcss-apply

• Added: image-set() support
  (via postcss-image-set-polyfill)
  (#373 - @SuperOl3g)
• Added: new auto-deactivation rule in features map
  (#369 - @Semigradsky)

• Added: system-ui keyword to define current System font-size
  (via postcss-font-family-system-ui)
  (#342 - @JLHwung)
• Added: new auto-deactivation rules in features map
  (#345 - @Semigradsky)

• Added: new rgb() & hsl() functional notation
  (via
  postcss-color-rgb &
  postcss-color-hsl
  )
  (#330 - @dmarchena)

• Added: attribute case insensitive support
  (eg: [data-thing=stuff i] { to be able to select all data-thing
  attribute, without having to thing about the case of the value)
  (#306 - @Semigradsky)

• Added: @apply support (definitions limited to :root selector)
  (#291) - @pascalduez)

• Added: overflow-wrap fallback
  (#280)
  • @MattDiMu