RED. Measured on R761 after the reader landed: non-whitespace preservation was
1 283 393 characters against the source's 1 283 395. Two characters, and a
percentage would have let them pass -- a ratio of 0.999998 reads like rounding.
Located by a prefix/suffix scan rather than a diff: the whole loss is one `x)`
marking a `<sec>` that carries a label and nothing else.
The mechanism is this reader's own. A label-only section holds its label as a
PREFIX for the body line beneath it, the way `li` is handled in the HTML
reader; when no body line follows -- the next thing emitted is the following
section's heading -- the pending prefix is overwritten by the next one and the
label never reaches the text.
`sts-empty-label.xml` is the case, hand-written and small: a lettered point
with a body, then one with none, then the next titled section.
pytest -q: 1 failed, 1566 passed, 1 skipped.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
