Honer

Honer is a macOS utility that draws a visible border around the window that currently has focus. By continuously monitoring which window is active, it adds a colored outline that makes the focused pane stand out from surrounding windows. The application runs as a background service and updates the border in real time as the user switches focus.

The tool is aimed at users who employ tiling window managers, where windows are often arranged without clear visual separation, as well as individuals with accessibility needs who benefit from an explicit indication of the active window. It requires macOS 10.9 (Mavericks) or later and is distributed under the MIT license.

Although the project is marked stable, the README notes that recent versions of macOS may cause functionality issues, and it points users toward the Limelight project as a maintained alternative. The latest release can be downloaded from the project's GitHub releases page.