Comment 3 for bug 926791

Stewart Wilson (stewartw) wrote :

The correct behaviour here is to disable the launcher reveal when dragging windows across display edges. However, the mouse cursor should still be held briefly at the left and right edges, when travelling below the threshold velocity for cursor holds.

There are two holds at the display edge to overcome when travelling from right to left, the first to trigger the launcher reveal, and the second which allows the mouse to pass the edge. This second hold is also present when moving from left to right, to support targeting items near the edges of the display. For full details, please refer to the section Launcher-Targeting the Launcher in the multi-monitor spec:

When dragging a window, this cursor hold makes it easier to achieve semi-maximised window states on the shared edges between displays, and feels much lighter when not combined with the initial launcher reveal hold.

This is similar to the following bug:
These bugs have not been marked as duplicates because of the mention of the mouse getting stuck here, requiring the user to drop the window and restart the drag.