In Ash, most windows use ResizeHandleWindowTargeter create the area where a pointer or touch event can be used to resize the window. (Some use EasyResizeWindowTargeter or a derivative.) These can either be drags or double clicks for single-axis "maximize".

This works fine in Mash for the area outside the window but not for the area inside the window (1dip). That inside area is important for when a window is flush against the side of a display.

Notes:
1. only applies when window is restored, not maximized or fs

2. 1dip drag area in that case eats input events, e.g. clicks don't go to the webpage. See https://jsfiddle.net/evanstade/f053gsor/5/ -- create restored window, put cursor at rightmost pixel of window (may be easier if you first drag the right side of the window to be flush with edge of display), click. The webpage doesn't get the click.

2b. I see some inconsistency when trying the same test, but in the window frame, where hovering the rightmost pixel highlights the window caption close button, and triple clicks get through to it but not single or double.

conclusion: we should just be able to inset the client area by 1dip on left, right and bottom when restored without loss of functionality.