或者這不是障礙嗎？ for transform HTML or XHTML into PDF, see the 正如此
In this "imagined context" there are another barrier?
for transform HTML or XHTML into PDF, see
正如此在此發表評論，EPUB v3 .1+標準采用 CSS-break ，
因此，當 CSS工作組（2018 ... 2019年快照）時，這將自動發生決定CSS-break規範是穩定的還是廣泛實現的。
Most of EPUB readers produce ugly layout, and EPUB3
format without CSS3-break can't produce good or
professional-quality layout as PDF format... So, there are a lot of
scepticism about EPUB. Please, lets imagine the future in
this question (!), please ignore this kind of
CSS3break is to improve EPUB layout, and this question is supposing (is correct?) that PDF layout and EPUB layout will be equivalent when printing.
工作定義：此處的上下文是在 HTML5 + CSS3break和/或EPUB用於官方文檔 Digital_preservation“rel =”nofollow noreferrer“> 數字保存 觀點。例子：
Open structure and semantic: HTML5 offers a lot of tags for organize contents in a structured way and some semantics. Adding RDFa layer (with good standards as SchemaOrg) we can express any kind of semantic for official contents, from scientific articles (ScholarlyArticle) to contracts and legislation.
In November 2017 ~1,229,000,000 of URLs was using some kind of HTML+semantic, mainly Microdata and some other variants of the RDFa standard. Digital content ecosystem need HTML, CSS, RDFa, MathML, etc. (not PDF).
When a digital preservation initiative need to "zip all content in to a file", can use EPUB standard.
Conclusion: only attractives (plans to enhance all with CSS3-break), no barriers to use EPUB for digital preservation.
Open Science: today they use a XHTML-like format, the JATS standard, as official digital preservation format for scientific articles, and the "content matrix" that generats all other formats (EPUB and HTML automatic but PDF not)... There are many "official preservarion repositories" as PMC and SciELO. PubMed Central offerts ~5 million articles in all formats, including ~5 million of EPUB.
Sample PMC2150930 article in all formats: ugly layout EPub and good PDF, and HTML variants as HTML classic layout, HTML modern layout.
There are plans to migrate from JATS to ScholarlyArticle in minor publisher houses, to use directly HTML5+RDFa as official digital preservation format.
Conclusion: only attractives, no barriers to use EPUB+CSS3break for digital preservation in open science.
Open Government and Digital transparency: today all contries are migrating its "official documents", that are articles in the government gazettes, from PDF to HTML and/or EPUB... They are going up the stairs in the 5-star deployment scheme for Open Data. It is a transition: e.g. European countries National Law, Brazilian Official Gazzete, UK legislation, etc. today are producing "twin documents" (HTML and PDF) from a xml matrix.
... With CSS3break they will need only HTML as matrix. In fact, there are plans to migrate from "ugly non-standard XML" to good XHTML5 (plus RDFa when necessary) in minor publisher houses, so HTML ecosystem as "content matrix", and EPUB as official digital preservation format.
Conclusion: only attractives, no barriers to use EPUB+CSS3break for digital preservation in open government.