resizing repeating segment not consistent

One segment one bar long, at bar 2. Mark repeating.

Try to resize the right side. Nothing happens. (This is probably
OK, I think.)

Try to resize the left side. The segment actually resizes, but
what's happening on the screen makes it look as though you are
dragging it from side to side. There's no way to tell what you're
actually accomplishing until you let go of the mouse to see how
it came out.

I'm not sure this wasn't a problem in 1.0, so this may be a
newly-discovered bug rather than a regression.