Sticky sections + collapsed borders sampler

#329702833 Status: New Priority: P3 Area: Blink / Table paint

Goal

What to check

When sticky table parts move during scroll, collapsed borders should stay attached. This page now includes baseline repros plus extra probes for section/row/cell sticky and trickier geometry.

Demo 1 -- Sticky thead (first section) original repro

sticky thead, top: 0
scrollTop=0, scrollLeft=0

Content under sticky header.

If top border detaches, text peeks through.

Demo 2 -- Sticky tfoot (last section) non-first section

sticky tfoot, bottom: 0
scrollTop=0, scrollLeft=0

Content above sticky footer.

If top/footer borders detach, red bleeds through.

Demo 3 -- Thead + tfoot sticky combined

thead top:0 + tfoot bottom:0
scrollTop=0, scrollLeft=0

Both top and bottom sticky border paths active.

Demo 4 -- Sticky middle tbody section probe

middle tbody sticky, top:0
scrollTop=0, scrollLeft=0

Middle section sticky probe.

Demo 5 -- Sticky tr row probe

sticky table row, top:0
scrollTop=0, scrollLeft=0

Sticky row probe.

Demo 6 -- Sticky td cell probe

sticky table cell, top:0
scrollTop=0, scrollLeft=0

Sticky cell probe.

Demo 7 -- Rowspan/colspan + sticky tfoot span geometry

sticky tfoot with colspan/rowspan above
scrollTop=0, scrollLeft=0

Span geometry probe.

How to use this page

  1. Run demos 1-3 first (known baseline cases).
  2. Then run demos 4-7 (section/row/cell/span probes).
  3. Main symptom to watch: collapsed borders separating from sticky parts while scrolling, then snapping back after scroll settles.