Hebrew Gap Analysis

W3C Group Draft Note

More details about this document
This version:
https://www.w3.org/TR/2024/DNOTE-hebr-gap-20240920/
Latest published version:
https://www.w3.org/TR/hebr-gap/
Latest editor's draft:
https://w3c.github.io/hlreq/gap-analysis/
History:
https://www.w3.org/standards/history/hebr-gap/
Commit history
Editor:
(W3C)
Feedback:
GitHub w3c/hlreq (pull requests, new issue, open issues)

Abstract

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

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 the Hebrew script 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.

The editor's draft of this document is being developed in the GitHub repository Hebrew Language Enablement (hlreq), with contributors from the W3C Internationalization Interest Group. It is published by the Internationalization Working Group. The end target for this document is a Working Group Note.

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 03 November 2023 W3C Process Document.

1. Introduction

1.1 Contributors

This document was created by Richard Ishida.

All contributors to the Hebrew Language Enablement project can be found in the GitHub contributors list.

1.2 About this document

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 that people encounter when trying to use languages written in the Hebrew 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.

1.3 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 feature 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 Writing mode

In what direction does text flow along a line and across a page? (See the Bidirectional text section if the basic direction is right-to-left.) If the script uses vertically oriented text, what are the requirements? 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?

2.2 Bidirectional text

If the general inline direction is right-to-left, are there any issues when handling that? Where the inline direction of text is mixed, is this 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?

#30 :dir lacks wide support

Languages: he 1

This issue is applicable to all languages with RTL orthographies.

Style sheets need to add special rules for RTL styles if they are not supported by logical properties or values.

One approach is to create a second style sheet which, when pulled into an HTML page, overrides styles in the main style sheet with settings for RTL text. This approach is not ideal because it requires maintaining the styles in two separate locations, which can therefore get out of synch, and it requires explicit addition of a call to the second style sheet in every page that will support RTL text.

The :dir() pseudo-class avoids these issues by allowing the content author to include the RTL variations in the same style sheet as the others. However, it is not yet supported by all major browser engines.

For more details, see this GitHub issue, which is being used to track this gap. Please add any discussion there, and not to this issue.

#27 Need support for dirname attribute

Languages: he 3

This issue is common to all RTL scripts.

When strings are passed around, some applications don't receive or use information about the appropriate base direction to use for those strings when they are rendered as part of a page.

This can lead to text being incorrectly aligned, and to text within a sentence or paragraph being incorrectly ordered. Some of this can be addressed by using heuristics to detect the direction first-strongly directional character in the string, but some strings can fail such heuristics.

HTML's dirname attribute, which is supposed to pass information with form data about direction of the text isn't fully interoperable across major browser engines.

FIXED !
This gap is now fixed. For details, see this GitHub issue.

#26 Logical CSS shorthands needed

Languages: he 1

This issue is common to all RTL scripts.

Adoption of logical keywords such as -start and -end, rather than -left and -right needs to be completed.

For margins, padding, block size, border colour, width & style, logical keywords such as margin-inline-start or margin-block-end are widely supported by major browsers in their simplest forms (such as those just mentioned). However, logical properties are not well supported in shorthands such as margin-block or margin-inline or the margin property. The lack of support for shorthands is significant, since they are expected to have high use.

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

#25 Support for isolating formatting characters lacking in some browsers

Languages: he 3

This issue is applicable to all RTL scripts.

For support of bidirectional plain text, the Unicode Standard provides a number of formatting characters, which include RLI, LRI, PDI and FSI. See an explanation of how these work.

Although markup should be used most of the time in HTML pages, there are parts of an HTML document that don't support markup, such as the title element and title, alt, and other attributes. These characters can be necessary for managing inline runs of such text.

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

3. Glyph shaping & positioning

3.1 Fonts & font styles

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?

3.2 Context-based 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?

#16 Difficulties in highlighting diacritics

Languages: he 2

It is occasionally useful to give the diacritics a different color, for example for the purpose of teaching. For an example of how it would appear, see the Hebrew Wikipedia article Holam, which shows diacritics in a different color using images. Because of the diacritics' combining nature, it's a bit complicated to insert them between separate tags, but possible by writing HTML entities instead of explicit characters. The bigger problem is that modern browsers either ignore this formatting or show it incorrectly.

A test can be found at this js fiddle, which displays different diacritics.

3.3 Letterform slopes, weights, & italics

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?

#29 It should be possible to slant glyphs to the left for italics/oblique

Languages: he 2

This issue is applicable to Arabic/Persian, Hebrew, & N'Ko.

There should be means available to control the direction in which 'italicised' or 'oblique' text slants, since some users prefer such text to slant to the left, following the flow of the text itself (in the same way that italicisation does in English).

For more details, see this GitHub issue, which is being used to track this gap. Please add any discussion there, and not to this issue.

3.4 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?

3.5 Case & other character transforms

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?

4. Typographic units

4.1 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?

4.2 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.)

#17 Doubling-click around maqaf doesn't behave as expected

Languages: he 2

Hebrew text is generally similar to Latin text in regard to what is selected when the user double-clicks on some text. The only issue to note is selecting and moving through text that includes the character maqaf, the Hebrew hyphen. It should behave like a hyphen.

It appears to be implemented correctly in Chrome and Firefox with regards to double clicking, moving through words using Ctrl-Arrow while editing text in a textarea, and long-pressing on mobile devices, but on some other platforms it may behave incorrectly, given that it's not a global punctuation character like the Latin hyphen.

5. Punctuation & inline features

5.1 Phrase & section boundaries

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?

5.2 Quotations & citations

Are there any issues when dealing with quotations marks, especially when nested? Should block quotes be indented or handled specially?

#18 q element produces incorrect quotation marks when language changes

Languages: he 2

This issue is common across all languages that use the q element and use different quote marks than English.

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.

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.

For example, quotations work fine in a sentence that is all in the same language. In this example the markup:

<span lang="he">אחת <q>שתיים <q>שלוש</q></q></span>

will produce the expected result:

אחת ”שתיים ’שלוש’”

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

אחת “two ‘three’

whereas it should be:

אחת ”two ’three’

Specs: This incorrect behaviour was initially introduced 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.

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.
Gecko, Blink, and Webkit fail. The quotation marks are those associated with the quotation rather than those associated with the surrounding text.

i18n test suite, Multilingual nesting.

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

#15 By default, browsers don't show low+high quotation marks

Languages: he 2

See the requirements.

The <q> elements don't currently show low quotation marks for Hebrew at all. Example can be found at a Hebrew Q fiddle. Firefox shows “ for the beginning and ” for the ending. Chrome uses the plain " and ' characters. Chrome's behavior is acceptable, although not very elegant. Firefox's behavior is definitely wrong. It would be good to have the elegant low and high quotes as the standard, or at least to have " and ' characters as the standard.

5.3 Emphasis & highlighting

How are emphasis and highlighting achieved? If lines or marks are drawn alongside, over or through the text, do they need to be a special distance from the text itself? Is it important to skip characters when underlining, etc? How do things change for vertically set text?

5.4 Abbreviation, ellipsis & repetition

What characters or other methods are used to indicate abbreviation, ellipsis & repetition?

5.5 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.)

5.6 Text decoration & other inline features

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?

5.7 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?

6. Line and paragraph layout

6.1 Line breaking & hyphenation

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?

6.2 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?

6.3 Text 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.)

#19 Browsers apply extraneous spaces when letter-spacing

Languages: he 2

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

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.

Here is an example in Hebrew.

Screenshot 2021-01-25 at 07 51 58

For more details, see this GitHub issue, which is being used to track this gap. Please add any discussion there, and not to this issue.

6.4 Baselines, line-height, etc

Does the browser support requirements for baseline alignment between mixed scripts and in general?

6.5 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?

6.6 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?

7. Page & book layout

7.1 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.

7.2 Grids & tables

Does the script have special requirements for character grids or tables?

7.3 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.)

7.4 Page headers, footers, etc.

Are there special conventions for page numbering, or the way that running headers and the like are handled?

7.5 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.

8. Other

8.1 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).

8.2 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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