Docking oddities

Sidewise doesn't dock properly on 64bit Linux. It always leaves blank space on one side of its window (sometimes both sides). If I move it to the left edge of the screen, then grab the left edge of Chrome to drag it left towards Sidewise, Sidewise detaches itself from the left side of the window, leaving white space on one or both sides of the Sidewise window, and does not attach to the Chrome window.