“Debian Bullseye has relatively few major changes which are visible to users,” according to Raspberry Pi. “There are some under-the-hood changes to file systems and printing, but most of the changes are patches and upgrades to existing applications and features. However, over and above the changes in Debian itself, the Bullseye version of Raspberry Pi OS has a number of significant changes to the desktop environment and to the support for Raspberry Pi hardware.”
Changes include:
KMS (kernel mode-setting) video driver, an experimental option before, is now the standard video driver in this release. This means that any application written using standard Linux display APIs should run on Raspberry Pi without modification.
The driver used to access camera modules has been replaced with the standard Linux libcamera API, making it easier for third parties to develop camera hardware and software.
When software updates are available, the user will get an on-screen notification. “With security threats and vulnerabilities being found and fixed in operating systems on a daily basis, it has never been more important to keep your computer up to date. Hopefully this is now as easy on a Raspberry Pi as on any other computer,” according to Rasbpberry Pi.
The update notification above, and existing notifications such as when a USB stick is removed, the power supply is low or the firmware detects an error, are now shown at the top right corner of the screen in a new consistent way, and will automatically hide after a while.
Out in the Raspberry Pi community, early adopters are already commenting that later versions of Raspberry Pi 4 are automatically up-clocked from 1.5GHz to 1.8GHz when the new operating system is installed.
Amongst operating system changes that are more cosmetic to the end-user, the window manager is now ‘mutter’ (illustration above) instead of the ‘openbox’. Mutter is a compositing window manager, and this has been used to add some visual tweaks to the on-screen interface including shading added behind the boarders windows and animation as windows open and close – at the expense of additional processing and memory load. It “can only run properly on a Raspberry Pi with 2Gbyte or more. As a result, on Raspberry Pis with less than 2Gbyte, the older openbox window manager is still used,” according to Raspberry Pi. (Oh the slippery slope from function to beauty. Ed)
All of the desktop components and applications are now using version 3 of the GTK+ user interface toolkit. This technical change has been made while minimising disruption to the look and feel of the on-screen user interface. The most obvious is the new appearance of tabbed interfaces, said Raspberry Pi.
The file manager has been simplified to have buttons for icons and list only, with other options accessed through the View menu.
Custom PC magazine will automatically be available free through the Bookshelf application.
Chromium web browser, now at version 92, and has been optimised to use Raspberry Pi video playback hardware acceleration.
“With a major upgrade, we recommend downloading a new image, reinstalling any applications, and moving your data across from your current image,” according to Raspberry Pi. “Debian major version upgrades contain a lot of changes, and it is very easy for some small tweak made somewhere in the system to be incompatible with some change you have made, and you can end up with a broken system and a Raspberry Pi that won’t boot.”