Seelen UI vs Starling

Seelen UI is a free customization layer for organizing windows and changing the Windows desktop interface. It is designed for Windows 10 and Windows 11 and does not modify system files or fully replace the desktop. Its automatic tiling manager offers BSPWM, Tall, Wide, and Grid layouts, plus float, stack, monocle, and per-app rules. The shell includes a dock, scriptable toolbar, start menu, custom Alt+Tab switcher, and window previews. Background options include MP4 and WebM video, interactive HTML/CSS/JS, music-synced visuals, and collections assigned to monitors or workspaces. Built-in widgets include media controls, clock and calendar, system monitoring, notifications, Wi-Fi, and Bluetooth. The media module supports pausing, resuming, and skipping tracks with most music players. Documentation covers themes, widgets, plugins, and development; community support is directed through Discord, repositories, and other channels. Modified, debloated, or custom Windows installations are not recommended because removed components or disabled services may cause errors.

Starling is a desktop environment with a 2D workspace and an optional 3D city workspace. Its Linux desktop combines a Wayland compositor, window manager, dock, spaces, and nine first-party apps in a session alongside the existing desktop. It runs native Wayland clients and X11 apps, can launch applications installed on the machine, and includes an App Store for installing more. The supported Linux package target is Ubuntu 26.04 LTS on amd64; the desktop can also run through Ubuntu 26.04 on WSL2. Starling’s Windows shell supports Windows 10 and 11 on x64, and its page says Store apps keep working. The shell, apps, build tools, documentation, and host code are open source under Apache 2.0, and the product is free. The Linux session runs without elevated privileges. Starling labels the desktop an early preview and says users should expect rough edges, missing pieces, and bugs. Its Windows preview installer installs per user without administrator privileges, but is unsigned and prompts SmartScreen on first run.