Modern Greek Gap Analysis

W3C Group Draft Note

More details about this document
This version:
https://www.w3.org/TR/2023/DNOTE-grek-gap-20230614/
Latest published version:
https://www.w3.org/TR/grek-gap/
Latest editor's draft:
https://w3c.github.io/eurlreq/gap-analysis/grek-gap
History:
https://www.w3.org/standards/history/grek-gap
Commit history
Editor:
(W3C)
Feedback:
GitHub w3c/eurlreq (pull requests, new issue, open issues)

Abstract

This document describes and prioritises gaps for the support of Modern Greek on the Web and in eBooks. In particular, it is concerned with text layout. It checks that needed features are supported in W3C specifications, in particular HTML and CSS and those relating to digital publications. It also checks whether the features have been implemented in browsers and ereaders. This is a preliminary analysis.

Status of This Document

This section describes the status of this document at the time of its publication. A list of current W3C publications and the latest revision of this technical report can be found in the W3C technical reports index at https://www.w3.org/TR/.

This document describes and prioritises gaps for the support of Modern Greek on the Web and in eBooks. In particular, it is concerned with text layout. It checks that needed features are supported in W3C specifications, in particular HTML and CSS and those relating to digital publications. It also checks whether the features have been implemented in browsers and ereaders. It is linked to from the language matrix that tracks Web support for many languages.

This document is an individual contribution, and is not currently a work item in any group, however, you can contact the Internationalization Working Group for more information. We welcome contributions to this and/or other documents.

This document was published by the Internationalization Working Group as a Group Draft Note using the Note track.

Group Draft Notes are not endorsed by W3C nor its Members.

This is a draft document and may be updated, replaced or obsoleted by other documents at any time. It is inappropriate to cite this document as other than work in progress.

The W3C Patent Policy does not carry any licensing requirements or commitments on this document.

This document is governed by the 2 November 2021 W3C Process Document.

1. Introduction

The W3C needs to make sure that the needs of scripts and languages around the world are built in to technologies such as HTML, CSS, SVG, etc. so that Web pages and eBooks can look and behave as people expect around the world.

This page documents difficulties people encounter when trying to use the Greek language in the Modern Greek script on the Web.

Having identified an issue, it investigates the current status with regards to web specifications and implementations by user agents (browsers, e-readers, etc.), and attempts to prioritise the severity of the issue for web users.

A summary of this report and others can be found as part of the language matrix.

For a description of the Greek script see the (non-W3C) page Greek, which summarises aspects of the orthography and typographic features, including relevant Unicode characters and their use.

1.1 Work flow

This version of the document is a preliminary analysis

Gap analysis work usually starts with a preliminary analysis, conducted quickly by one or a small group of experts. Then a more detailed analysis is carried out, involving a wider range of experts. The detailed analysis may involve the development of tests, in order to illustrate issues and track results for browsers. The next phase is ongoing maintenance. It is expected that the resulting document will not be frozen: as gaps are fixed, this should be noted in the document. It is also possible that new gaps are noticed or arise, and they can be added to this document when that happens.

1.2 Prioritization

This document not only describes gaps, it also attempts to prioritise them in terms of the impact on the local user. The prioritisation is indicated by colour.

Key:

It is important to note that these colours do not indicate to what extent a particular features is broken. They indicate the impact of a broken or missing feature on the content author or end user.

Basic styling is the level that would be generally accepted as sufficient for most Web pages. Advanced level support would include additional features one might expect to include in ebooks or other advanced typographic formats. There may be features of a script or language that are not supported on the Web, but that are not generally regarded as necessary (usually archaic or obscure features). In this case, the feature can be described here, but the status should be marked as OK.

The decision as to what priority level is assigned to a described gap is down to the experts doing the gap analysis. It may not always be straightforward to decide. If a given section in this document refers to more than one feature that is broken, each with different impacts on Web users, the priority for the section should be the lowest denominator.

A cell can be scored as OK if the feature in question is specified in an appropriate specification, and is supported by user agents. A specification that is in CR or later and has two implementations in 'major' browsers will count. This means that the feature may not be supported in all browsers yet. (At some point in the future we may try to distinguish, visually, whether support is available in a specification but still pending in major browsers or applications.)

2. Text direction

See also General page layout & progression for features such as column layout, page turning direction, etc. that are affected by text direction.

2.1 Vertical text

Are the script requirements for vertically oriented text met? What about if you mix vertical text with scripts that are normally only horizontal? Do you need a switch to use different characters in vertical vs. horizontal text? Does the browser support short runs of horizontal text in vertical lines (tate-chu-yoko in Japanese) as expected? Is the orientation of characters and the directional ordering of characters supported as needed? See available information or check for currently needed data.

#11 CSS Writing-modes sideways values not implemented

This issue is applicable to most languages.

Text that is normally written horizontally may need to be written vertically for special effects (the spine of a book, table column headings, etc). Typographically, it is simply horizontal text that is rotated.

The GAP
The CSS feature defined in Writing Modes Level 4, which is in CR, provides a solution using sideways-lr|sideways-rl values of the writing-mode property.

There is no way to do this effectively until browsers support the new CSS properties.

writing-mode:vertical-lr/rl is not appropriate for achieving this, because of things such as wrong locations for line start and end, and incorrect direction of line wrapping, not to mention the implications for glyph rotation.

Only Gecko supports these values. Blink and WebKit do not.

Tests & results
interactive test, sideways-rl is supported in browsers

interactive test, sideways-lr is supported in browsers

Action taken
ChromiumWebKit

Outcomes
tbd

Priority
Support is needed sooner rather than later, since many people keep writing tutorials or explainers that show how to do this using the currently supported writing-modes values. However, the currently supported values only work properly for CJK languages, and produce incorrect results for normally horizontal scripts unless used in the simplest way possible (for example, line breaking and text alignment break things).

The sideways values were moved from CSS Writing Modes 3 to level 4 because implementation support was there for the values needed for CJK. However, CSS Writing Modes 4 went to CR almost immediately with the expectation that support for the sideways features would follow soon.

2.2 Bidirectional text

If this script runs right-to-left, are there any issues when handling that? Is bidirectional text adequately supported? What about numbers and expressions? Do the Unicode bidi controls and HTML markup provide the support needed? Is isolation of directional runs problematic? See available information or check for currently needed data.

3. Characters and phrases

3.1 Characters & encoding

Are there any character repertoire issues preventing use of this script on the Web? Do variation selectors need attention? Are there any other encoding-related issues? See available information or check for currently needed data.

3.2 Fonts

Do the standard fallback fonts used in browsers (eg. serif, sans-serif, cursive, etc.) match expectations? Are special font or OpenType features needed for this script that are not available? See available information or check for currently needed data.

3.3 Font styles, weight, etc

This covers ways of modifying the glyphs, such as for italicisation, bolding, oblique, etc. Do italic fonts lean in the right direction? Is synthesised italicisation problematic? Are there other problems relating to bolding or italicisation - perhaps relating to generalised assumptions of applicability? See available information or check for currently needed data.

3.4 Glyph shaping and positioning

Does the script in question require additional user control features to support alterations to the position or shape of glyphs, for example adjusting the distance between the base text and diacritics, or changing the glyphs used in a systematic way? Do you need to be able to compose/decompose conjuncts, or show characters that are otherwise hidden, etc? See available information or check for currently needed data.

3.5 Cursive text

If this script is cursive (eg. Arabic, N’Ko, Syriac, etc), are there problems or needed features related to the handling of cursive text? Do cursive links break if parts of a word are marked up or styled? Do Unicode joiner and non-joiner characters behave as expected? See available information or check for currently needed data.

3.6 Transforming characters

Does your script need special text transforms that are not supported? Does your script convert letters to uppercase, capitalised and lowercase alternatives according to your typographic needs? Do you need to to convert between half-width and full-width presentation forms? See available information or check for currently needed data.

#15 Greek uppercase transforms fail for some characters

Converting text to uppercase requires special behaviour for some Greek characters.

Specs: The text-transform property is defined in CSS Text Module Level 3.

The spec includes mention of the need for user agents to tailor the transforms for a particular language:

The UA must use the full case mappings for Unicode characters, including any conditional casing rules, as defined in the Default Case Algorithms section of The Unicode Standard. If (and only if) the content language of the element is, according to the rules of the document language, known, then any appropriate language-specific rules must be applied as well. These minimally include, but are not limited to, the language-specific rules in Unicode’s SpecialCasing.txt.

Tests & results: i18n test suite, case conversion, Greek These tests focus on monotonic Greek as used for modern texts.

  • Gecko:Mozilla/5.0 (Macintosh; Intel Mac OS X 10.15; rv:98.0) Gecko/20100101 Firefox/98.0
  • Blink:Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/99.0.4844.51 Safari/537.36
  • Webkit: ✅❌ The basic conversions work, but the special Greek rules are not applied. See below. Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/605.1.15 (KHTML, like Gecko) Version/15.3 Safari/605.1.15
Issues with WebKit:
  1. transform: uppercase doesn't cause Greek words that are all uppercase to lose tonos.
  2. transform: uppercase doesn't convert diphthongs with tonos on the first character so that the tonos is removed but a dialytika is added above the second character in the diphthong.
  3. text-transform: uppercase should cause a disjunctive eta in a Greek sentence keeps its tonos diacritic, but the test is inconclusive because none of the other tonos marks is removed.

Browser bug reports: WebKit

Bugs reported for characters not used in modern Greek: BlinkGecko

3.7 Baselines & inline alignment

Does the browser support requirements for baseline alignment between mixed scripts and in general? See available information or check for currently needed data.

3.8 Grapheme/word segmentation & selection

This is about how text is divided into graphemes, words, sentences, etc., and behaviour associated with that. Do Unicode grapheme clusters appropriately segment character units for your script? When you double- or triple-click on the text, is the expected range of characters highlighted? When you move through the text with the cursor, or backspace, etc. do you see the expected behaviour? (Some of the answers to these questions may be picker up in other sections, such as line-breaking, or initial-letter styling.) See available information or check for currently needed data.

3.9 Punctuation & other inline features

Are there specific problems related to punctuation or the interaction of the text with punctuation (for example separation of punctuation from previous text, but allowing no line break between)? Are there issues related to handling of abbreviation, ellipsis, or iteration? Are there problems related to bracketing information or demarcating things such as proper nouns, etc? See available information or check for currently needed data.

3.10 Text decoration

This is about ways of marking text (see also specific sections dedicated to quotations and inline notes/annotations). Is it possible to express emphasis or highlight content as expected? Bold, italic and under-/over-lines are not always appropriate, and some scripts have their own unique ways of doing things, that are not in the Western tradition at all. Text delimiters mark certain items or sections off from the main text, such as book names in Chinese, quotations, head markers in Tibetan, etc, and often involve the use of punctuation. Is there any behaviour that isn't well supported, such as overlines for numeric digits in Syriac? Are there issues about the positioning or use of underlines? Some aspects related to the drawing of lines alongside or through text involve local typographic considerations. Do underlines need to be broken in special ways for this script? Do you need support for additional line shapes or widths? Does the distance or position of the lines relative to the text need to vary in ways that are not achievable? Are lines correctly drawn relative to vertical text? See available information or check for currently needed data.

3.11 Quotations

Are there any issues when dealing with quotations marks, especially when nested? Should block quotes be indented or handled specially? See available information or check for currently needed data.

#22 q element produces incorrect quotation marks when language changes

This issue is common across all languages that use the q element.

When an English page contains a quotation in another language, the quotation marks used around that quotation (and inside it for embedded quotes) should be the English ones – not those of the language of the quotation. The same applies for other languages.

The GAP
Currently, if the language of the quotation is declared on the q tag in HTML and that tag has a lang attribute, browsers instead set the quotation marks based on the language of the quote.

Quotations work fine in a sentence that is all in the same language. For example, the markup for this Georgian text:

<span lang="ka">ერთი <q>ორი <q>სამი</q></q></span>

will result in:

ერთი „ორი «სამი»“

However, if the quote is in English and lang="en" is added to the first q tag, the result becomes:

ერთი “two ‘three’”

whereas it should be:

ერთი „two «three»“

This is the case for Gecko, Blink, and WebKit.

Tests & results
Interactive test, When an embedded quote is in a different language, the quotation marks should be those of the main body, even if the language of the quote is declared using a lang attribute.

i18n test suite, Multilingual nesting.

Action taken
This incorrect behaviour was initially dictated by the HTML specification. issue 3636 was raised to change the spec. In the end the entire section was removed from the HTML spec, and HTML now relies on CSS for this behaviour.

css-content says that If a quotation is in a different language than the surrounding text, it is customary to quote the text with the quote marks of the language of the surrounding text, not the language of the quotation itself., however it is non-normative text.

Issue 5478 Open, requests that this be made normative, and has been agreed by the CSS WG.

Browser bug reports: GeckoBlinkWebkit

Outcomes
tbd

Priority
Marking this as advanced because it's possible, though not always as convenient, to use Unicode characters instead of the q element.

3.12 Inline notes & annotations

The ruby spec currently specifies an initial subset of requirements for fine-tuning the typography of phonetic and semantic annotations of East Asian text, including furigana, pinyin and zhuyin fuhao systems. Is is adequate for what it sets out to do? What other controls will be needed in the future? What about other types of inline annotation, such as warichu? (For referent-type notes such as footnotes, see below.) See available information or check for currently needed data.

3.13 Data formats & numbers

If the script has its own set of number digits, are there any issues in how they are used? Does the script or language use special format patterns that are problematic (eg. 12,34,000 in India)? What about date/time formats and selection - and are non-Gregorian calendars needed? Do percent signs and other symbols associated with number work correctly, and do numbers need special decorations, (like in Ethiopic or Syriac)? How about the management of personal names, addresses, etc. in web pages: are there issues? See available information or check for currently needed data.

4. Lines and Paragraphs

4.1 Line breaking

Does the browser capture the rules about the way text in your script wraps when it hits the end of a line? Does line-breaking wrap whole 'words' at a time, or characters, or something else (such as syllables in Tibetan and Javanese)? What characters should not appear at the end or start of a line, and what should be done to prevent that? See available information or check for currently needed data.

See also hyphenation below.

4.2 Hyphenation

Is hyphenation used for your script, or something else? If hyphenation is used, does it work as expected? (Note, this is about line-end hyphenation when text is wrapped, rather than use of the hyphen and related characters as punctuation marks.) See available information or check for currently needed data.

4.3 Text alignment & justification

When text in a paragraph needs to have flush lines down both sides, does it follow the rules for your script? Does the script need assistance to conform to a grid pattern? Does your script allow punctuation to hang outside the text box at the start or end of a line? Where adjustments are need to make a line flush, how is that done? Do you shrink/stretch space between words and/or letters? Are word baselines stretched, as in Arabic? What about paragraph indents, or the need for logical alignment keywords, such as start/end, rather than left/right? See available information or check for currently needed data.

4.4 Letter spacing

Some scripts create emphasis or other effects by spacing out the words, letters or syllables in a word. Are there requirements for this script/language that are unsupported? (For justification related spacing, see below.) See available information or check for currently needed data.

#23 Browsers apply extraneous spaces when letter-spacing

This issue applies to all languages that use letter-spacing.

Various orthographies use letter-spacing to stretch words or phrases. This may be for a purely visual effect, but may also carry semantics, for example in languages such as German and Hebrew it is a way of emphasizing text.

When letter-spacing is applied, authors expect the spaces to occur only within the text to which it is applied.

The GAP
Currently browsers that apply letter-spacing do so by adding a space after every letter in the text that is tracked. This results in a superfluous space at the end of the range, which creates an inappropriate gap before the following text. Letter spacing at the end of a line makes the line look misaligned in justified or right-justified text. It also has implications for text that has other styling, such as an outline or a coloured background, at the same time as being stretched.

Example in German: 87327736-5c89f780-c52c-11ea-8d22-7b994925d61a

Gecko, Chrome, and Webkit put the letter spacing after a letter even when it is at the end of a line, which makes the line look misaligned in justified or right-justified text.

For now, content authors have to work around the problem by also applying a negative margin to remove the trailing space. This is problematic not only because it requires additional work on the part of the author every time letter-spacing is used, but it is quite likely that the author is unaware that they need to do this, or indeed how to do it.

Tests & results
Interactive test Letter-spaced text should create no space on the outside of the selection

Action taken
CSS issue 1518 The css-text specification requires letter-spacing to only insert space within the selection, not outside, so it is the browser implementations that need to be fixed. However, there is discussion around how to manage backward compatibility if browsers change their implementations.

Outcomes
tbd

Priority
Given that a workaround is possible, though not really acceptable, this is prioritised as an advanced issue.

4.5 Lists, counters, etc.

The CSS Counter Styles specification describes a limited set of simple and complex styles for counters to be used in list numbering, chapter heading numbering, etc.The rules plus more counter styles (totalling around 120 for over 30 scripts) are listed in the document Ready-made Counter Styles. Do these cover your needs? Are the details correct? Are there other aspects related to counters and lists that need to be addressed? See available information or check for currently needed data.

#18 greek-lower-modern counter style not supported

Customisable counters are needed for many languages.

There is no way for users to create local counter styles that are not built in to the browser, and users also often want to tweak the counter style in some way (esp. the prefix/suffix).

The lower-greek counter style is defined in the CSS Counter Styles Level 3 specification, however this style is relevant for mathematical texts. The greek-lower-modern style described in Ready-made Counter Styles is more commonly used for normal text in Greece.

For more details, see this GitHub issue, which is being used to track this gap.

The following is Greek-specific additional information.

CSS2.1 included the lower-greek keyword, and all major browsers support the lower-greek counter style but none support the greek-lower-modern style.

The CSS Counter Styles spec allows users to create their own counter styles, but the feature is only implemented by Firefox at the moment.

Effectively, this means that there isn't a good greek counter style feature available for authors.

Tests & results:

  1. Simple alphabetic
  2. Greek script

4.6 Styling initials

Does the browser or ereader correctly handle special styling of the initial letter of a line or paragraph, such as for drop caps or similar? How about the size relationship between the large letter and the lines alongide? where does the large letter anchor relative to the lines alongside? is it normal to include initial quote marks in the large letter? is the large letter really a syllable? etc. Are all of these things working as expected? See available information or check for currently needed data.

5. Page & book layout

5.1 General page layout & progression

How are the main text area and ancilliary areas positioned and defined? Are there any special requirements here, such as dimensions in characters for the Japanese kihon hanmen? The book cover for scripts that are read right-to-left scripts is on the right of the spine, rather than the left. Is that provided for? When content can flow vertically and to the left or right, how do you specify the location of objects, text, etc. relative to the flow? For example, keywords 'left' and 'right' are likely to need to be reversed for pages written in English and page written in Arabic. Do tables and grid layouts work as expected? How do columns work in vertical text? Can you mix block of vertical and horizontal text correctly? Does text scroll in the expected direction? Other topics that belong here include any local requirements for things such as printer marks, tables of contents and indexes. See available information or check for currently needed data.

5.2 Footnotes, endnotes, etc.

Does your script have special requirements for footnotes, endnotes or other necessary annotations of this kind in the way needed for your culture? (There is a section above for purely inline annotations, such as ruby or warichu. This section is more about annotation systems that separate the reference marks and the content of the notes.) See available information or check for currently needed data.

5.3 Page headers, footers, etc.

Are there special conventions for page numbering, or the way that running headers and the like are handled? See available information or check for currently needed data.

5.4 Forms & user interaction

Are vertical form controls well supported? In right-to-left scripts, is it possible to set the base direction for a form field? Is the scroll bar on the correct side? etc. See available information or check for currently needed data.

6. Other

6.1 Culture-specific features

Sometimes a script or language does things that are not common outside of its sphere of influence. This is a loose bag of additional items that weren't previously mentioned. This section may also be relevant for observations related to locale formats (such as number, date, currency, format support).

6.2 What else?

There are many other CSS modules which may need review for script-specific requirements, not to mention the SVG, HTML, Speech, MathML and other specifications. What else is likely to cause problems for worldwide deployment of the Web, and what requirements need to be addressed to make the Web function well locally?

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