Cinnamon uses Muffin, a fork of the GNOME 3 window manager Mutter, as its window manager from Cinnamon 1.2 onwards.

Workspace OSD

Workspaces are "persistent" in Cinnamon. This means you can create a workspace whenever you want by clicking the "+" button and it will remain there until you decide to delete it. You can log off or even reboot, your workspaces will remain the way you defined them.

In Cinnamon you can give them a name. This allows you to define distinct and memorable environments and to separate and gather your windows according to your activities. When you switch workspaces, the workspace name appears on the screen. So you always know where you are.

The Workspace OSD (On-Screen-Display) is also configurable. You can set its duration, its position on the screen and whether you want it to show up or not.

Window Quick-List

The Window Quick-List is a new applet which lists all your windows across all workspaces. Scale also received improved keyboard navigation, so whether you prefer to find your windows by name or by looking at them, you can do so quickly and easily in Cinnamon.

Finally, both Scale and Expo are now also available as applets (as opposed to hot corners). This means they can be added wherever you want in the panels, in complement or replacement of the window quick-list.

Notifications Applet

When you add the notifications applet to your panel it keeps track of any notification you didn't dismiss. Cinnamon notifications are ephemeral; Either you click them and they disappear immediately or they disappear by themselves after a few seconds.

The notifications applet acts like a tray which collects the notifications you didn't click on. This is particularly handy when you're busy doing something else and you just happened to see a notification in the corner of your screen but didn't have time to read it, or when you're away and you want to catch up with what happened during your absence.

Alt-Tab Thumbnails And Window Previews

The Alt-Tab window switcher is now configurable. Cinnamon 1.6 features the following switchers: * Icons (default, similar to Cinnamon 1.4) * Icons + Thumbnails * Icons + Window Previews * Window Previews

"Window Previews" shows a preview of the selected window while switching with an effect similar to the Compiz Fusion switcher. The window in question comes to the front of the screen and is displayed prominently. If the theme defines it, the window can also be highlighted with an outline border/color.

Improved Sound Applet

Music lovers will enjoy some of the improvements in the Sound Applet. The layout was reworked to give the cover artwork more space. The volume slider now features a visible percentage and no longer controls amplification past 100% (although this was handy in Cinnamon 1.4, it was confusing and led to people experiencing sound saturation). The applet now also comes with tooltips and mute buttons for the sound and the microphone (accessible via the right-click menu).

Backgrounds Selection & Nemo Integration

Although it can be used with Nautilus or other file browsers, Cinnamon's default file browser is now Nemo. Cinnamon will eventually handle all visible layers of the Gnome desktop and provide an integrated experience, not only in terms of window and workspace management, but also in terms of file browsing, configuration and desktop presentation. Cinnamon 1.6 comes with tight integration for Nemo and a brand new backgrounds selection screen.

What's New:

Desktop freezes

On supported hardware Cinnamon now uses a newer "cogl" API. This change is known to prevent some of the causes of desktop freezes observed in earlier releases.

In case of a freeze or if you need to restart Cinnamon for any reason, you can now do so via a keyboard shortcut. The default key combination is Ctrl+Alt+Escape. Pressing this combination of keys restarts nemo and cinnamon-settings-daemon in case they had crashed, and launches a brand new instance of the Cinnamon desktop. Unlike Ctrl+Alt+Backspace which terminates your session and brings you back to the login screen, Ctrl+Alt+Escape simply restarts Cinnamon itself, which means your session is exactly as it was, you don't lose any work and all your windows and applications remain open.

Responsiveness, load times and CPU usage

A huge amount of work was done to review the CPU usage in various parts of Cinnamon and many improvements were made. Performance was gained by optimizing how Cinnamon reacts to particular events and reducing the number of tasks or repeated tasks it performs. The menu, for instance, is refreshed about 6 times as less as before… signals resulting from connecting a USB device are grouped together and lead to 1 action, reducing 4 concurrent reactions into a single one. The docinfo part of Cinnamon, which handles "recent files", was optimized a lot. We found out tiny features such as generating thumbnails for "recent" files in the application menu were very expensive in resources and dropping them led to significant reductions in CPU usage. Un-necessary calculations in the window management part of Cinnamon could also be dropped, leading to reduced idle CPU usage (about 40% reduction in the number of CPU wakes per second).

Loading times were also reviewed (this covered Cinnamon and MDM) and found to be excellent, except for the case where Cinnamon is loaded for the first time after a computer restart or shutdown. Whereas a normal Cinnamon initialization would typically take between 0 and 2 seconds, the very first one could take up to 40 seconds on some of our test systems. The reason was a lack of HDD read-cache, especially when it came to Gio appinfo and icon themes data. To reduce this initial load time, Cinnamon 2.6 introduces a preload mechanism which loads themes and app info asynchronously earlier on during the boot sequence. Distributions using non-standard icon themes can add them to /etc/cinnamon/preload/iconthemes.d/.

Finally, information was added to Looking glass logs to report the Cinnamon startup time as well as to indicate how long each enabled applet took to start.

Multi-monitor and multi-panel support

Support for multiple monitors was improved. Better window list actions and new keybindings allow you to move windows to other monitors (Super+Shift with arrow keys by default). But the most significant improvement is that you can now have multiple panels and place them across multiple monitors.

Applets are better than before at running multiple instances of themselves and some of them got smarter to accommodate multi-monitor/multi-panel setups. For instance a window list applet won't show you windows from another monitor if that monitor has a panel with its own window list.

Screensaver

Up until version 2.6 "cinnamon-screensaver" was no more than a "screen locker". It locked the screen but didn't actually play any animation.

This is changed now as it gained support for XScreenSaver modules and HTML5 screensavers.

Panel improvements

Panels can now be added/removed/configured individually and moved to different positions across one or multiple monitors.

They have a new way of hiding/showing themselves called "intelli-hide" :)

The way their left/center/right zones are defined was redesigned and they are now able to center applets in the middle whether left and right zones contain applets or not.

Applet improvements

A new "inhibit" applet was introduced which allows you to quickly turn notifications off or to disable power management. This applet is handy when performing presentations, to prevent unwanted notifications to pop up, to prevent the screen from dimming brightness or the screen to get locked. You no longer need to modify your power settings, you can just temporarily disable all that.

The inhibit applet also tells you when another program is disabling power management. This is useful to know whether the programs you're using are telling Cinnamon you're actually "doing" something (my favorite media player "mpv" for instance isn't…) :)

The user and network applets were improved slightly. The sound applet received better PulseAudio support, it detects output devices more accurately and now features a slightly revamped UI and a new application mixer (so you can change the sound level for individual applications straight from the applet).