6.4.9879.0

Start and Action center

• You can now disable the search and Task View button
• The Action center has been placed in the notification area
• New battery indicator

File Explorer

• Favorite folders can now be pinned to Home in File Explorer
• OneDrive now uses selective sync, no more Smart Files

User Interface

• Animations have been refined
• More icons have been replaced with new versions
• The 3 dots-icon has been replaced with a hamburger menu icon, works the same
• Dialogs in WinRT are now windowed

Internet Explorer

• A feedback icon has been added next to options prominent in the interface
• Extended standard and API support
  • Support for Content Security Policy
  • GamePad API support has returned (as seen in Internet Explorer Developer Channel)
  • CSS Transforms - preserve-3d support
  • JS Arrow function
  • JS iterators
  • JS Symbols
  • Media Queries Level 4: Interaction Media Features
  • Selection API Support
  • WAV Audio Support
  • ES6 Built-ins (Math, Number, String and Object)
  • ES6 Object Literal Enhancements
  • ES6 Promises
  • ES6 Classes
  • ES6 Spread
  • ES6 Template Strings
  • ES6 Proxies
  • ES6 WeakSet
• Experimental Features Dashboard has been added under about:flags
• The User Agent String has been altered
• EdgeHTML has been added

Settings

• New panels, settings and options
  • Storage Sense has been added to the main menu
  • You can now back-up settings to OneDrive (not the same as sync)
  • You can now change your background through this app
  • Under "Privacy", Cortana options have been added

System

• Touch gestures on a touchpad are now built-in and universal across all Windows devices
• Improvements to multi-monitor support have been made
• MKV support has been improved

Apps

• Insider Hub has been added as a new app, a news portal for Windows Insiders
• OneDrive has been removed as an app
• You can now pin the search app to the taskbar and start screen
• Windows Feedback
  • Feedback can now be sorted on trending, number of "Me Too's" and most recent
  • The apps will take you back to the category after posting feedback
  • Bug fixes when using search
  • Screenshot button is now easier to find

Other features

• "System compression" has been added to Disk Cleanup as a new option

And further

• Universal scrolling has been enabled again

6.4.9879.5

And further

• Unknown fixes and enhancements