A regression the previous commit introduced, found in review. The checkbox
driving the collapsed nav carried `hidden`, which is `display:none`, which
removes it from the tab order AND from the accessibility tree. A <label> is
not focusable on its own -- the checkbox it labels is what carries focus -- so
at <=900px the navigation could be clicked and reached no other way, and the
accessibility snapshot contained neither the checkbox nor any of the 25 links.
The toggle is now visually hidden but focusable at narrow widths, and
display:none at wide ones. Keeping display:none on the wide side matters:
merely un-hiding it puts focus on an invisible control whose label is
display:none, which is its own wart.
Measured at 390, 900, 901 and 1280, because the regression lives on one side
of a media query. At 390 and 900 the tab order is brand -> navtoggle, the
toggle is focusable, the a11y tree carries a checkbox node, and Space takes
visible nav links 1 -> 26. At 901 and 1280 the toggle is display:none, not
focusable, absent from the a11y tree, and tab runs straight through the 26
links -- desktop identical to before. 0 of 23 pages scroll horizontally at
320, 390 and 1280, so the absolutely-positioned 1px input introduces nothing.
WHAT IS WORTH MORE THAN THE FIX, and why doc-site.md gains a paragraph rather
than the code gaining a comment: my probe for the previous commit counted
VISIBLE nav links. That answers "does operating the toggle reveal the links" --
correct and complete for a mouse -- and is silent on whether any non-mouse
route exists. It could not have seen this, however sharp the visibility
instrument was. Last round's lesson was that a measurement which cannot
distinguish the two states is not a measurement; this round adds the half it
was missing: a measurement of the wrong PROPERTY is not a measurement either.
checkVisibility fixed the visibility instrument; it does not turn a visibility
count into an operability check. The instrument here is tab order, .focus()
and the accessibility snapshot.
Gates: 1378 rust, 26 node --test, 16 playwright (3 skipped, webkit OPFS), all
three check-comment-runs modes, 3462 site links / 0 broken, 0 nested anchors,
0 of 23 pages overflow at 320/390/1280.
improvise-djoo
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Edward Langley
c0b786cf0d