Just as KDE 3.5 was intended to be a stabilizing, long-term release, the primary goal of KDE 4.5 is to fix outstanding bugs and increase stability. Users will not be blown away by the new features, but there are a few worth noting. Last week I installed the release candidate for KDE 4.5 from the Kubuntu repositories and took it for a spin.

New Notification Area

KDE 4.5 continues to improve upon the desktop’s notification system, creating a new D-Bus-based protocol that provides notifications for KDE and Gnome applications in a uniform fashion. The developers have also created a new system tray with more consistent icons.

The notification area now presents a less intrusive popup and includes past notification messages in tabs according to application. Notification area menus and widgets can now be rendered by the desktop, regardless of the toolkit used by the application itself.

KWin Improvements

KWin, KDE’s window manager, has added support for window tiling, much like the Ion window manager. Users can snap in new windows side-by-side, below, and above other windows on the screen, rearrange them, and resize them, all within the tiling system.

Another new, less-advertised feature is the reinstatement of the blur effect into KDE’s composite desktop effects. This allows transparent or translucent portions of a window (or the entire windows, depending on the theme) to blur the backgrounds behind them. This feature was present in early KDE 4 releases but was then removed due to bugs. Unfortunately, it appears as though the current release will not work correctly on many graphics cards, which is probably why it is not listed among the main features. Another improvement is that the Aurorae theme engine will now support the same tabbed window system that was introduced into Oxygen in KDE 4.4. Aurorae themes will also be integrated into the same selection menu with other window decorations, making usage of them more seamless. The Window Decorations section in System Settings has been moved to a new section called Workspace Appearance, which includes Desktop Theme and Splash Screen settings.

Konqueror Webkit Support

There is now an official Webkit K-part for Konqueror, which integrates many of the standard Konqueror features like ad blocking, password storage, plugins, and more. Konqueror’s default rendering engine will continue to be KHTML, from which Webkit is derived, but users will have the option to install kpart-webkit from their Linux distribution’s repositories. Webkit is the rendering engine used in Apple’s Safari, iPhone, iPad, and Google Chrome.

New Plasma Features

Plasma, KDE’s desktop shell, has a few new features added in SC 4.5. Among them are the preview button in Folderview. Instead of hovering over a folder and automatically giving you a popup access window, hovering your mouse will show an “up arrow” button that gives the same functionality, making it less intrusive. KDE has also added many new features and fixes to KDE games, admin tools, and other included software. KDE 4.5 is available for many operating systems, including Linux, FreeBSD and other Unix variants, Windows, and Mac OS X. Most Linux distributions provide updated binaries through their software repositories. You can also download KDE from the project’s website and build it from source. KDE is free and open source software, and the new version 4.5 is expected to be released today, August 4.