The "white bar" was the footer's near-white background painting
over the bottom of the sidebar. The footer is fixed at body level
with ``left: 0; right: 0`` so it spans the full viewport — its
``rgba(255, 255, 255, 0.97)`` background renders as essentially
white over the sidebar's ``rgb(240, 242, 246)`` gray, producing a
visibly different strip at the bottom of the sidebar (this is what
the diagnostic GREEN tint marked as ``stAppViewContainer``-shaped
because that is the element directly behind it).
Pixel-sampled the bottom row to confirm:
y=860 over sidebar → (240, 242, 246) (gray)
y=870 over sidebar → (255, 255, 255) (footer-painted white)
Fix: in the iframe JS that mounts the footer on ``<body>``, measure
``[data-testid="stSidebar"].getBoundingClientRect().right`` and set
the footer's (and help popover's) ``left`` to that offset with
``setProperty(..., 'important')`` so it beats the ``left:0!important``
fallback in CSS. A ``ResizeObserver`` on the sidebar plus a
``window.resize`` listener keep the offset in sync when the sidebar
collapses or expands.
Sidebar collapsed (width 0 or off-screen) clamps to 0 → footer goes
flush-left as before. Also dropped the no-op ``min-height`` on the
view container from the previous attempt; ``stAppViewContainer`` is
transparent, so stretching it never painted anything.
Verified by injecting the same offset on the live page: bottom row
at y=890 is now ``(240,242,246)`` over the sidebar and only turns
white at x=255 where the content area begins.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
Michael
c942b8aa19