When a CAPC browser (Chrome, IE) window is resized, the vertical scroll bars on the browser window disappear after the window is shrunk to less than half the width of the screen.
When the browser window is less than the minimum width we support, the document body stops resizing horizontally (it stays at the minimum width) and as a consequence the right side of the window is clipped off display. The first thing to go will be the vertical scroll bar. We do not display a horizontal scroll bar when this happens because of assorted browser bugs which come and go when the horizontal scroll bar is on the entire window. Currently the minimum width we support is 1130 pixels (we document 1280, but we change the value from between 1024 and 1180 depending on the minimum widths certain elements require in the page such as the context pickers from release to release depending on changes to those elements).