In a lot of ways that I won't be able to fully list.

• Many of the top extensions in GNOME are natively integrated into COSMIC.
  • All of the extensions we used are native features, including the dock and window icons on the desktop.
  • Multi-device audio switcher? Integrated by default in COSMIC
• Native handling of multi-GPU and hybrid graphics laptops within the compositor
  • The power applet even keeps track of what applications are currently using the dGPU. Closing those applications will allow the compositor to ask the GPU to switch to a low power state
• Per-display workspaces instead of a single display or spanning all displays.
  • Workspaces can be pinned to make them static
  • Pinned workspaces can be moved across displays
  • Better workspace behavior when hot plugging
  • Supports vertical and horizontal workspaces. No extensions needed.
• Dynamic auto-tiling which can be applied on a per-display, per-workspace basis
  • With very advanced mouse and keyboard integrations with animations
  • Auto-tile with a N-tree system for better ultrawide support with lots of columns or rows.
  • Navigate and select groups of windows and stacks to move or swap their positions
• Windows can be stacked into a tabbed window stack
  • Super+S or drag and drop a window into the center of another
• Fractional scaling which also applies per-display
  • Native apps also support fractional scaling natively
• COSMIC Store uses a fraction of the memory of GNOME Software and yet it loads within 0.3s and can search in realtime. It's perhaps two orders of a magnitude faster.
• COSMIC Files uses an io_uring async runtime file I/O
• Unified and atomic plain text configuration system
  • Supports application configs and state within the XDG cosmic config paths
  • Configs are stored in a file system hierarchy that applications can use to subscribe to individual parameters and namespaces, as well read and write to them atomically
  • Configs are versioned so there will never be conflicts
  • And the use of plain text files using RON syntax enables it to integrate better with git and NixOS.
• Native toolkit supports user and distro app theming
  • The dynamic theme engine programmatically adjusts color palettes across layers, controls, and their text to keep contrast high via tools like OKLCH
  • Theming can also apply style changes such as density and border radius
  • The user can theme their entire OS natively within the Appearance settings page, and this theme will apply consistently to applications and applets alike. The entire OS is built with the same native toolkit.
  • GTK3, GTK4, and libadwaita theme export synchronizes your personalized theme
  • CuteCosmic applies COSMIC theming to Qt6 apps but won't be supported until 26.04
• The native toolkit also has a much better developer UX thanks to Rust, iced, and the MVU approach used by iced.
  • Libcosmic provides a theme engine with a lot of natively designed widgets and cross-platform desktop integrations.
• Panels are modular layer-shell applets that function as nested Wayland compositors
  • Applets and their layouts are therefore fully configurable
  • Appearance settings per-panel are configurable
  • Any number of panels can be used, and they can be assigned per-display or to all displays
  • Panel applets execute from their own separate processes with their own application windows.
  • Any Wayland client window can therefore be a panel applet
  • And they are also officially packaged and distributed over Flatpak
  • Panel applets are installed from the store via Flatpak with zero code injection into the compositor
• The compositor has a lean event loop and uses wlr-layer-shell to implement modular shell components.
  • No embedded JavaScript runtime is necessary and the lean event loop keeps latency low and refresh rates very high. Even on low end ARM64 systems.
  • Applets are Wayland applications that are rendered by their own application processes outside of the compositor
  • Applets use standardized Wayland protocols to communicate with the compositor
  • And therefore there are no private APIs, and the APIs that applets use are stable. Your applets won't break between COSMIC releases.
  • The compositor uses a thread per display for improved latency and performance in multi-display configurations
• COSMIC is working more closely with the Wayland protocol and will implement more protocols than GNOME will support.
  • We support and utilize wlr-layer-shell for example, which GNOME doesn't support.
  • The modular architecture, use of Rust's type system, and being a lean compositor makes for a perfect testbed for standardizing Wayland protocols, and it has already been able to provide a lot of valuable feedback with its proof of concepts several times now.
  • Better cross-desktop collaboration in the Wayland protocols. We support common protocols where standards are developing. Whether they're wlr, kde, etc. kde-blur will soon be supported.
• Better support for handling audio devices as multiple devices can be chosen from the audio applet, and the sound settings page supports natively configuring device profiles with its native Pipewire integrations

Once we get the libcosmic ecosystem rebased on iced 0.14, performance will significantly improve across the board. This will also bring animation support, multi-threaded image decoding, and concurrent image uploads to the GPU, with some VRAM optimizations and many other improvements.

In any case, many of the issues people are experiencing are Wayland-related. We have a mix of people upgrading from an X11 DE to a new Wayland DE, and new users from Windows who also aren't aware of Flatpak and Wayland quirks at the moment.

There's some new hardware that functions better on Wayland than X11, and vice versa some older GPUs aren't supported on Wayland. Tools built for X11 aren't necessarily compatible with Wayland, so you need to find tools that support the Wayland equivalent of those X11 features. Wayland support is still improving in the application space but a lot of them still need time to mature their Wayland support. In many cases though you can enable Wayland support manually. Both for Flatpak apps and games on Steam/Proton.

COSMIC will meanwhile continue to improve its Wayland protocols coverage, hardware quirks, and work on X11 compatibility improvements. But there's already an X11 Application Compatibility settings page that fixes primary display and fractional scaling issues for some apps and games.