montab

montab (short for "monitors tabs") is a sidebar that docks to the left or right edge of every monitor and shows a live preview of every window on that monitor, all the time. No hovering, no cycling. You glance at the panel and you can see which terminal is the one still chewing through your test suite.

The previews aren't screenshots! They're DWM thumbnails - the compositor already holds every window's rendered frame, so the panel just asks it to draw those frames into a rectangle. No capture, no encoding, no polling loop. That's why they're genuinely live instead of refreshed on a timer, and why it sits at ~0% CPU when idle. It also reserves the work area through the AppBar API so maximized windows don't slide under it, and tracks windows with SetWinEventHook instead of polling EnumWindows.

Other bits: one panel per monitor, listing only that monitor's windows - drag a window to another screen and its tile follows. Minimized windows drop into a second section as compact strips, so nothing vanishes on you. Clicking the active window's tile shoves it below the others without minimizing. Hover a preview for ~0.7s and you get a x5 magnifier you can pan with the mouse; Ctrl+wheel is persistent zoom. Drag to reorder, drag the inner edge to resize.

Pure Win32 - no WPF, no WinUI, definitely no Electron. C# on .NET 11 with NativeAOT and CsWin32 for the P/Invoke, ~3.4k lines, one ~2 MB exe with zero dependencies, ~5 MB private working set with a panel on every monitor.