- A poem is a container of verse, and stores its range of verse ocn,
  - its verse are the citable units with ocn.

- A note in the last verse of a poem previously was not gathered into
  the endnotes section, this now is fixed

Format 2.0 -> 2.1: the property is an addition, the poem is not a
citable object (but contans a range of objects), its verse are
(individual citable objects), and every reader checks the major version.
A 2.0 database reads as having no ranges.

(assisted by Claude-Code)

The markup documents ~[* note ]~ and ~[+ note ]~ as editor's notes, each
a separately numbered series, and a bare ~[ note ]~ which sisu put in
the asterisk series. They are included as notes. Each series is numbered
through the document, *1, *2 ... and +1, +2 ..., apart from the author's
notes.

(assisted by Claude-Code)

need a character to split filenames on in certain circumstances.
there problems with use of a colon in filenames, which is legal on posix
but not on Windows."~" fits the bill better being legal on every
filesystem of interest and is unreserved in rfc 3986, needing no escaping in a url.

The reference abstraction is renamed, its content unchanged. Over
the sample collection two filenames move and nothing else does: the
abstraction and database digests are identical, the archive's
members and their sizes are unchanged, and only the member order
shifts, "~" collating after letters where ":" sorted before them. The
document's epub dc:identifier is a v5 uuid derived from the uid, so it
changes for those filenames.

Every document's uid changes in the search database (spine.search.db).

(assisted by Claude-Code)

The ja and pl translations were mended in the sample set, so the two
divergences this script asserted by name are gone. It failed and named
every stale expectation, which is what it was for.

The reference set is regenerated with two files affected:
live-manual.ja.ssp and live-manual.pl.ssp.

(assisted by Claude-Code)

format 2.0, source.digest covers every markup file, the sha256 over one
line per markup file, "<sha256> <filename>", sorted by filename.

source.digest was the sha256 of the master file as read, before any
insert. This is right for a .sst, which is the whole document. For a
.ssm with inserts .ssi (containing the substantive part of a documents
text) this is close to meaningless.

Considered change of meaning (rather than an addition) and given the
major part of the format version with it: 1.1 becomes 2.0, in the .ssp
header line and in the database's schema.version row together.
A 1.x reader refuses a 2.0 artefact, which is what that check is for.

- Sorted, so the value does not depend on the order a filesystem hands
  back a directory.
- By filename (rather than by path), so it does not depend on where the
  pod sits, which is the property the pod rebuild comparison rests on:
  a pod unzipped elsewhere must still give the same abstraction.
  Within one language every markup file lives in one directory, so a
  filename identifies it.

Each line is checkable on its own against a digests.txt line or a files
row, which the single value was not. The whole is reproducible with
sha256sum and sort, and was verified that way for a one file document
and for a twenty file one.

An unreadable file is named in the digest rather than skipped. The parse
has failed elsewhere by then, and a digest that quietly left a file out
would claim the document is something it is not.

The reference abstractions are regenerated. Two lines change in each and
no others: the version, and the digest.

(assisted by Claude-Code)

reference abstraction follows live-manual's mended headers

The sample's catalogues were regenerated and its nine translated headers
mended, so those nine abstractions change. Two lines each for ca and es,
which is the source digest alone and no metadata at all: their headers
came back exactly as they were. Four to six for the rest, where a
copyright line drops its "Copyright (C)" prefix to follow the English,
and where de, pt_BR and ro gain a licence in their own language.

live-manual.en.ssp is unchanged, being the language translated from, and
so are the other twenty seven documents, byte for byte.

(assisted by Claude-Code)

The sample pod now lists pt_BR, so the document has a tenth
language.

No other document's reference is touched; the other twenty six
are byte identical.

(assisted by Claude-Code)

Four things, not visible in an error count:

- Images had no alt text, even where markup carried the text, and the
  field alt text is present, incorrectly used in code; fixed as the alt.

  { sm_tux.png 64x80 "Gnu/Linux - a better way" }image

  an image with nothing to say for itself gets alt=""

- Images with no dimensions were incorrectly written width="0"
  height="0", fixed

- Accessibility metadata, which EPUB Accessibility 1.1 requires:
  schema:accessMode, accessibilityFeature and accessibilityHazard, plus
  accessModeSufficient and accessibilitySummary, which epubcheck does
  not test for; used by
  - readers looking for a book it can use,
  - anyone distributing into the EU.
  Every value is derived from the document, not asserted: a document
  with no images says so, one whose images all carry alt text claims
  alternativeText and textual sufficiency, one where an image says
  nothing claims neither.
  Nothing claims WCAG conformance, which would be a claim about an
  evaluation that has not happened.

- DPUB-ARIA roles beside the structure spine already knew about.
  doc-toc, doc-endnotes, doc-bibliography, doc-glossary and doc-index on
  the sections, doc-noteref on a note reference and doc-footnote on the
  note it points at. "doc_endnotes" as a class name means something to a
  stylesheet and nothing to a reading system. Not doc-biblioentry: DPUB-
  ARIA 1.1 deprecated it. These are plain ARIA, so the html gets them
   too.

Also dealt with here:
- Spine makes certain sections such as endnotes, bookindex, ... and a
  heading that has a name for itself cannot share the same name, if it
  does the name is now disambiguated, disambiguated. (disambiguation
  similar to that used for a repeated anchor tag)

- Endnote anchors fixed to use "id" (being one unique tag in the
  document that is target of every reference to it)instead of obsolete
  form (they were <a name="note_1">. "name" on an <a>).
  Book index markers keep "name": the same marker sits on every object
  an entry names, 296 times in one document, and those are markers of
  where a term occurs rather than distinct targets.

(assisted by Claude-Code)

epubcheck 5.3.0 over the 35 sample epubs went from 1302 remaining errors
to none. The six causes for those remaining errors fixed here.

most of the count was one of them:

- Tables (1123 errors, 86%) where the writer emitted obsolete
  attributes, removed in 2014; table also now in div instead of a
  paragraph. also fixed:

- Navigation (115). Every level 4 heading's nav entry ended "#0", the
  ocn of an object that has no ocn and so no id.

- Duplicate ids (37). (from three unrelated sources).

- The publication identifier (27 warnings). dc:identifier was a
  hardcoded hex string, not a UUID, and the same one in all 35 files,
  so two documents in one library collided. It is now UUID v5 over the
  document's own uid: a real RFC 4122 identifier, stable across builds
  and distinct per document.

- Image manifest entries (15). media-type was "image/" plus the file
  extension, giving "image/jpg", which is not a media type; epubcheck
  reads it as a foreign resource and wants a fallback. There is now a
  mapping, which also covers svg and webp. Item ids came from the file
  basename, and "2bits_02_01-100.png" gave an id starting with a digit,
  which is not an XML name; ids are now prefixed and sanitised.

- An ocn resolving to no segment (9). A poem block and its first verse
  share one ocn; the verses are written into a segment and the block
  itself is not.

Also dropped from the package document: an xmlns:xsi that nothing
used, and a prefix declaration for the rendition vocabulary, which is
a reserved prefix and needed no declaring. The package now carries
xml:lang.

test-epub-validity.sh now allows no fatal and no error. Two NAV-011
warnings remain and are described in it. Three reference .ssp files
change, all of them the anchor tag disambiguation above.

(assisted by Claude-Code)

in error regex permitted a url to go past an endnote close delimiter,
fixed

(assisted by Claude-Code)