In Linux Mint 21 Blueman replaces Blueberry.
Just like Blueberry, Blueman is desktop-agnostic and integrates well in all environments.
Blueberry depended on gnome-bluetooth, which was developed exclusively for GNOME. In contrast, Blueman relies on the standard Bluez stack which works everywhere and can even be used or queried from the command line.
The Blueman manager and tray icon provide many features that weren't available in Blueberry and a lot more information which can be used to monitor your connection or troubleshoot Bluetooth issues.
Out of the box Blueman features better connectivity, especially when it comes to headsets and audio profiles.
In preparation for Linux Mint 21 the Blueman user interface was improved and received support for symbolic icons.
Upstream, Blueman and Bluez are actively developed and used in many environments.
The lack of thumbnails for some common file types was identified as a usability issue. To address it a new Xapp project called xapp-thumbnailers was started and is now featured in Linux Mint 21.
The project brings support for the following mimetypes:
The Sticky Notes application now has the ability to duplicate notes:
When Sticky Notes is told to pick different colors for newly created notes it no longer picks them randomly, but cycles through the color set to maximize the probability of each note having a different color.
The systray icon was restyled.
New notes are positioned relative to their parent.
Clicking the tray icon creates a new note if none are present.
Automated tasks are great to keep your computer safe but they can sometimes affect the system's performance while you're working on it.
A little process monitor was added to Linux Mint to detect automated updates and automated system snapshots running in the background.
Whenever an automated task is running the monitor places an icon in your system tray. Your computer might still become slow momentarily during an update or a snapshot, but with a quick look on the tray you'll immediately know what's going on.
Timeshift is now maintained as an XApp and its translations are done on Launchpad.
In rsync mode, it now calculates the required space for the next snapshot and skips it if performing that snapshot leads to less than 1GB free space on the disk.
Webp support was added to xviewer and thumbnailers.
Directory browsing was improved in Xviewer. Continuously pressing the arrow keys results in a smooth slideshow where enough time is given for each picture to be visible.
When Warpinator fails to find other devices, among other solutions, it now provides links towards its Windows, Android and iOS counterparts.
The Thingy bulk renamer application received UI improvements.
The WebApp manager supports additional browsers and custom browser parameters.
The biggest change in Cinnamon 5.4 is a major rebase of its window manager. Muffin is now based on Mutter 3.36 and its codebase is much closer to upstream than before.
When Muffin was forked from Mutter 3.2, the plan wasn't to develop a different window manager but simply to make Cinnamon compatible with all distributions of Linux by guaranteeing it had the same manager everywhere, no matter what version of Mutter was shipped.
Time flies. It's been 11 years since that fork. Over time both managers received features and improvements. Muffin caught up regularly by backporting Mutter changes into its codebase.
During that time the design of Mutter changed significantly though. Parts of Mutter were moved over to GNOME Shell and vice versa. This made it harder and harder to port some of the latest changes affecting Mutter over to Muffin because GNOME Shell and Cinnamon themselves are very different.
Muffin also received features and optimizations which weren't part of Mutter. Although these were beneficial to the Cinnamon desktop at the time, they also created a challenge when it came to catching up to Mutter improvements, and over time this became an issue.
After months of development, Muffin was completely rebased. Its particularities were reviewed. Some were dropped. Some were moved over to Cinnamon. To ensure easier rebases and backporting in the future, the priority was given to ensure the Muffin and Mutter codebases remained as close as possible.
To accommodate the new window manager the Display settings were backported from gnome-control-center into cinnamon-control-center. The display configuration which was previously handled by csd-xrandr (part of cinnamon-settings-daemon) was moved into Muffin.
In the past, applications could be rendered differently based on the technology they used. If a GTK application used a headerbar, its window was a CSD window and its titlebar and shadows were rendered using the GTK theme. If it didn't, its window was an SSD window and in this case its titlebar and shadows were rendered using the Metacity theme.
Although the Mint-X and Mint-Y themes did their best to make their GTK titlebars and shadows look as similar as their Metacity counterparts, in practice these were rendered by two different engines within Muffin and it introduced a slight visual disparity between the two types of windows.
In Cinnamon 5.4 all windows are now rendered with the GTK theme, whether they have a headerbar or not. Metacity themes are no longer used.
The GTK antialiasing, which is cleaner than the Metacity one, previously only benefited CSD windows. It's now used on all windows. Rounded corners look crispier.
Window animations were improved. The way they work changed under the hood. It's no longer possible to tune animations and to make your own like it was in the past, but the default set looks much cleaner than before and the global speed of animations is configurable.
Along with bug fixes Cinnamon 5.4 also features the following improvements:
Linux Mint 21 uses IPP, also known as Driverless Printing and Scanning (i.e. a standard protocol which communicates with printers/scanners without using drivers). For most printers and scanners no drivers are needed, and the device is detected automatically.
If your printer/scanner doesn't work properly disable driverless printing/scanning by removing the ipp-usb and airscan packages. Then install drivers from your manufacturer. For more information on printing and scanning: https://linuxmint-user-guide.readthedocs.io/en/latest/printers.html.
Note: HPLIP 3.21.12 is installed by default.
In Software Sources, the repository list, PPA list and key list support multiple selection. This allows several items to be removed at a time.
Uninstalling an application from the main menu (right-click -> uninstall) now triggers an evaluation of the application's dependencies. To protect the system from the removal of key components, if another package depends on the application, an error message is shown and the operation is stopped.
Uninstalling an application from the main menu now also removes dependencies of that application that were automatically installed and are no longer needed.
When you switch graphics cards using the NVIDIA Prime applet, the switch is now visible and you can cancel it if you change your mind.
Linux Mint 21 features a superb collection of backgrounds from Aaron Thomas, Aaron Burden, Calin Stan, Constantin, Denise Bossarte, Dave Hoefler, Evgeni Tcherkasski, Erwan Hesry, Erik Skof, Fakurian Design, Hello Lightbulb, Mike Enerio, Marek Piwnicki, Navi, Paul Carmona, Pawel Czerwinski, Roger Bradshaw, Raphael Lopes, Samuel Ferrara, Steve Johnson , W and Zetong Li.
Initial GTK4 support was added in the Mint-Y and Mint-X themes.
The Mint-X theme was redesigned. It's now built on SASS and supports applications which use dark-mode.
Linux Mint 21 features Cinnamon 5.4, a Linux kernel 5.15 and an Ubuntu 22.04 package base.
Linux Mint 21 will receive security updates until 2027.
Until 2024, future versions of Linux Mint will use the same package base as Linux Mint 21, making it trivial for people to upgrade.
Until 2024, the development team won't start working on a new base and will be fully focused on this one.