Mac OS X Developer Preview 4

Mac OS X Developer Preview 4 is the fourth and final Developer Preview of Mac OS X Public Beta. This build was demonstrated and distributed at the Apple Worldwide Developers Conference on 15 May 2000.

New features and changes

 * Setup has been slightly revamped in terms of design.
 * This build includes updates to the Aqua theme, making it resemble more to the Public Beta.
 * The Dock has been heavily revamped from Developer Preview 3, and now is more closer to the Public Beta. Some of these changes includes removing the application backgrounds and using a rectangular base to replace these backgrounds. The Dock is also translucent much like the menus and inactive applications. Items from the dock can also be removed, utilizing the animation of the item disappearing in a puff of smoke.
 * Dock magnification effects are enabled by default; this would be disabled by default in later builds and versions.
 * The application icon that replaced the Apple logo in Developer Preview 2 and before is now gone, and replaced with the name of the running application.
 * A country flag is included to the right of the "Help" of the menu bar so the user can quickly change languages.

Installation
On QEMU, this build has a bug where the CD-ROM driver doesn't work properly, causing the boot to hang. To install this build on QEMU, the installation media has to be booted from a hard drive media and not from the CD-ROM drive.