Implementing Chrome-Style Tab Tear-off in WinUI 3

Implementing Chrome-Style Tab Tear-off in WinUI 3 A deep dive into the pitfalls of implementing tab tear-off and re-docking in a WinUI 3 desktop app — why SC_DRAGMOVE doesn't work, how to use DWM Cloak to create windows without flicker, ghost tab indicators, and translucent window feedback. The End Result Drag a tab outside the window and a new window spawns, following your cursor. Hover over another window's tab bar and a ghost tab appears, while the dragged window turns translucent. Drop it and the tab merges at the exact position. Even single-tab windows can be dragged and merged into other windows. It's that feature you use every day in Chrome. Here's a rundown of the problems I hit while implementing this in WinUI 3 + C#, and how I solved them. 1. The Big Picture — Five Stages [PointerPressed] → [PointerMoved] → [Mouse Released] Detect drag start Outside window → TearOff Re-dock or drop Inside window → Tab reorder Stage Core Problem Solution 1. Drag detection Click vs. drag 8px Eu