It would appear that the contents index column (left column) should
presumably scroll independently, instead it scrolls with the main window in
which the content resides until it reaches it's end. This is extremely
annoying as it removes the ability to scroll the contents index to jump to
a portion of the contents and breaks the convention of user convenience
afforded by an independent scrollable index as available for large indexes
You are intending to maintain visibility of the column when the content is
scrolled past the header.
As this is the case, in that you are attempting to provide this column for
visibility regardless of the scrolling position of the content, as
specified, it should:
*cease scrolling this column when the content column is scrolled past the
header instead of as it is now, when the bottom of the index column is
In addition, independent scrolling functionality to said column in the form
of a scroll component or iframe is required.