Active Window Highlight

A clear, toolkit-independent focus indicator for Cinnamon — with an animated top bar, configurable frame and compositor-correct stacking.

Make the focused window unmistakable.
Keep your place across GTK, Qt, Wine and every other window on the desktop.

_{Configure the highlight live through Cinnamon's native extension settings.}

The extension draws at compositor level, so the highlight also works around Chromium, Qt, Wine and other non-GTK windows.

Highlights

• A configurable four-sided frame with independently controlled color, thickness, opacity and top-corner radius.
• An optional animated gradient bar above the focused window.
• Live settings through Cinnamon's native extension dialog.
• Support for normal windows, dialogs, modal dialogs and utility windows.
• Correct Muffin stacking: always-on-top windows and Cinnamon Shell surfaces remain above the highlight.

Highlight detail

The default frame is blue, 1 px wide and 95% opaque. Its top corners use a configurable 10 px radius while its bottom corners stay square to match Cinnamon's default window shape. Normal windows, dialogs, modal dialogs and utility windows are supported; fullscreen and minimized windows are intentionally ignored. All appearance options are exposed through Cinnamon's native extension settings.

Both the bar and frame are stacked immediately above the focused window. Other windows that Muffin keeps higher — including Always on Top windows — remain above the highlight. Cinnamon's start menu, panels, Expo, overview and other Shell surfaces remain above it as well.

Screenshot note: A “current window” capture may omit the animated top bar because it is a Cinnamon compositor overlay, not part of the application's own window surface. Use an area or full-screen capture when the complete highlight should be visible. This only affects screenshots, not the normal on-screen display.

Installation

git clone https://github.com/oss-singularity/cinnamon-active-window-highlight.git
cd cinnamon-active-window-highlight
./install.sh

Then disable and re-enable Active Window Highlight in System Settings → Extensions. The installer does not alter enabled extensions or restart Cinnamon automatically. To install a later version, run git pull in the checkout followed by ./install.sh again.

Run ./uninstall.sh to remove the extension files. Disable the extension before uninstalling it. User settings are deliberately retained.

Requirements

Cinnamon 5.8 or newer is supported. The extension has no separate runtime daemon and no toolkit-specific dependency.

Development

make check

The checks validate JavaScript syntax, compositor-stacking invariants, JSON schemas and shell scripts. Every push and pull request runs the same validation in GitHub Actions.

Origin and license

The animated trapezoid top-bar design and its gradient animation are derived from Active Window Indicator by fabiodamio, as distributed in Linux Mint's cinnamon-spices-extensions repository. This project adds the toolkit-independent four-sided frame, dialog support, a unified settings schema and corrected Cinnamon UI layering. See ATTRIBUTION.md.

Licensed under GPL-2.0-or-later. See LICENSE.