Apps similar to Sticky Previews include OnTopReplica, which is free and open source. Other options are WindowWatcher and Pocket Screen. In total there are three Window Managers like Sticky Previews for Windows and Mac.
A lightweight application that provides a real-time thumbnail replica of any window of your choice. OnTopReplica will stay always on top, allowing you to keep track of the original window while working and without having to keep the keyboard focus on it.
Italy
EU
WindowWatcher is a free hybrid window magnifier and remote control spy. It gives Windows the ability to have proper and resizable picture-in-picture support above and beyond Aero Snap. It's great for watching stuff like online TV, streams or Youtube playlists in a small...
Pocket Screen is a lightweight macOS menu bar utility that turns supported app windows into small, always-on-top picture-in-picture reference views.
Japan
