It’s been a while, but the Raspberry Pi OS has had a major version bump, taking this flavour of Linux for the diminutive computer to Debian Bullseye.

Debian Bullseye debuted in August, and the Raspberry Pi team admitted that getting its eponymous operating system updated had “taken a bit longer than we’d hoped”.

Bullseye will be supported for five years, and makes use of version 5.10 of the Linux kernel. It came just over two years since the last major Debian release, Buster. As well as the changes under the hood, the Raspberry Pi OS incarnation has a number of tweaks in support of the computer’s hardware and the OS’s desktop environment.

The most immediately visible is the move from the distinctly elderly GTK+ 2 to the GTK+ 3 toolkit for much of the UI. The GTK+ toolkit is used to draw standard user interface components in the case of the Pi, and the change is in recognition that an awful lot of Debian apps have moved on and so, therefore, must the desktop.

The change has been a while coming, and the Raspberry Pi team grumbled that GTK+ 3 had removed some features they’d been depending on, thus necessitating some workarounds to keep things look familiar (although the new appearance of tabbed dialogs might be a little jarring.)

A new window manager, called Mutter, has also replaced the openbox window manager. Mutter permits some appealing visual effects and animations, making things feel a bit more modern. The downside is that Mutter needs to draw the screen in memory before displaying it, meaning that Raspberry Pis with less than 2GB won’t get to join in the fun and will stick to openbox instead (and, heaven forbid, square-windowed tooltips).

As well as a general refresh of the applications that come with the distribution, the team has added a notification manager to the taskbar, currently showing error conditions, USB device alerts, iffy power levels, and, helpfully, an alert when updates are available. The…