#### 19.4.3 HTML Customization Variables

This table gives the customization variables which apply to HTML output only. A few other customization variables apply to both HTML and other output formats; see Other Customization Variables.

AVOID_MENU_REDUNDANCY

If set, and the menu entry and menu description are the same, then do not print the menu description; default false.

AFTER_BODY_OPEN

If set, the corresponding text will appear at the beginning of each HTML file; default unset.

AFTER_ABOUT

For HTML, when an About-element is output. If set, the corresponding text will appear at the end of the About element; default unset.

AFTER_OVERVIEW
AFTER_TOC_LINES

If set, the corresponding text is output after the short table of contents for AFTER_OVERVIEW and after the table of contents for AFTER_TOC_LINES; otherwise, a default string is used. At the time of writing, a </div> element is closed.

In general, you should set BEFORE_OVERVIEW if AFTER_OVERVIEW is set, and you should set BEFORE_TOC_LINES if AFTER_TOC_LINES is set.

BASEFILENAME_LENGTH

The maximum length of a base file name; default 245. Changing this would make cross-manual references to such long node names invalid (see HTML Cross-reference Link Basics).

BEFORE_OVERVIEW
BEFORE_TOC_LINES

If set, the corresponding text is output before the short table of contents for BEFORE_OVERVIEW and before the table of contents for BEFORE_TOC_LINES, otherwise a default string is used. At the time of writing, a <div ...> element is opened.

In general you should set AFTER_OVERVIEW if BEFORE_OVERVIEW is set, and you should set AFTER_TOC_LINES if BEFORE_TOC_LINES is set.

BIG_RULE

Rule used after and before the top element and before special elements, but not for footers and headers; default <hr>.

BODYTEXT

The text appearing in <body>. By default, sets the HTML lang attribute to the document language (see @documentlanguage ll[_cc]: Set the Document Language).

CASE_INSENSITIVE_FILENAMES

Construct output file names as if the filesystem were case insensitive (see HTML Splitting); default false.

CHAPTER_HEADER_LEVEL

Header formatting level used for chapter level sectioning commands; default ‘2’.

CHECK_HTMLXREF

Check that manuals which are the target of external cross-references (see @xref with Four and Five Arguments) are present in htmlxref.cnf (see HTML Cross-reference Configuration: htmlxref.cnf); default false.

COMPLEX_FORMAT_IN_TABLE

If set, use tables for indentation of complex formats; default false.

CONTENTS_OUTPUT_LOCATION

If set to ‘after_top’, output the contents at the end of the @top section. If set to ‘inline’, output the contents where the @contents and similar @-commands are located. If set to ‘separate_element’ output the contents in separate elements, either at the end of the document if not split, or in a separate file. If set to ‘after_title’ the tables of contents are output after the title; default ‘after_top’.

COPIABLE_ANCHORS

If set, output copiable anchors for the definition commands (see Definition Commands) and table commands (see Making a Two-column Table) where an index entry is defined. An anchor appears as a ‘¶’ sign that appears when you hover the mouse pointer over the heading text.

CSS_LINES

CSS output, automatically determined by default (see HTML CSS).

DATE_IN_HEADER

Put the document generation date in the header; off by default.

DEF_TABLE

If set, a <table> construction for @deffn and similar @-commands is used (looking more like the TeX output), instead of definition lists; default false.

DEFAULT_RULE

Rule used between element, except before and after the top element, and before special elements, and for footers and headers; default <hr>.

DO_ABOUT

If set to 0 never do an About special element; if set to 1 always do an About special element; default 0.

EXTERNAL_DIR

Base directory for external manuals; default none. It is better to use the general external cross-reference mechanism (see HTML Cross-reference Configuration: htmlxref.cnf) than this variable.

EXTRA_HEAD

Additional text appearing within <head>; default unset.

FOOTNOTE_END_HEADER_LEVEL

Header formatting level used for the footnotes header with the ‘end’ footnotestyle; default ‘4’. See Footnote Styles.

FOOTNOTE_SEPARATE_HEADER_LEVEL

Header formatting level used for the footnotes header with the ‘separate’ footnotestyle; default ‘4’. See Footnote Styles.

FRAMES

If set, a file describing the frame layout is generated, together with a file with the short table of contents; default false.

FRAMESET_DOCTYPE

Same as DOCTYPE, but for the file containing the frame description.

HEADER_IN_TABLE

Use tables for header formatting rather than a simple <div> element; default false.

HTML_MATH

Method to use to render @math. This can be unset, set to ‘mathjax’ (see MathJax Customization Variables), set to ‘l2h’, which has the same effect as setting L2H (see latex2html Customization Variables), or set to ‘t2h’, which uses tex4ht.

ICONS

Use icons for the navigation panel; default false.

If set, the associated value is prepended to the image file links; default unset.

INDEX_ENTRY_COLON

Symbol used between the index entry and the associated node or section; default ‘:’.

INFO_JS_DIR

(Experimental.) Add a JavaScript browsing interface to the manual. The value of the variable is the directory to place the code for this interface, so you would run the program as e.g. ‘texi2any --html -c INFO_JS_DIR=js manual.texi’ to place files in a ‘js’ directory under the output. This provides some of the functionality of the Info browsers in a web browser, such as keyboard navigation and index lookup. This only works with non-split HTML output.

The interface should provide an acceptable fallback in functionality if JavaScript or web browser features are not available. However, please be cautious when using this option, in case you do make your documentation harder to access for some of your users.

INLINE_CSS_STYLE

Put CSS directly in HTML elements rather than at the beginning of the output; default false.

JS_WEBLABELS
JS_WEBLABELS_FILE

Specify how to use a JavaScript license web labels page to give licensing information and source code for any JavaScript used in the HTML files for the manual. (See https://www.gnu.org/licenses/javascript-labels.html).

With the value ‘generate’ (the default), generate a labels page at JS_WEBLABELS_FILE, and link to it in the HTML output files. Only do this if actually referencing JavaScript files (either with HTML_MATH set to ‘mathjax’, or when using the experimental JS browsing interface when INFO_JS_DIR is set). With this setting, JS_WEBLABELS_FILE must be a relative file name.

With the value ‘reference’, link to the labels file given by JS_WEBLABELS_FILE in the output, and do not generate a labels file. This setting is useful if you separately maintain a single labels file for a larger website that includes your manual.

With ‘omit’, neither generate nor link to a labels file.

KEEP_TOP_EXTERNAL_REF

If set, do not ignore ‘Top’ as the first argument for an external ref to a manual, as is done by default. See Referring to a Manual as a Whole.

MAX_HEADER_LEVEL

Maximum header formatting level used (higher header formatting level numbers correspond to lower sectioning levels); default ‘4’.

MENU_ENTRY_COLON

Symbol used between the menu entry and the description; default ‘:’.

MENU_SYMBOL

Symbol used in front of menu entries when node names are used for menu entries formatting; default ‘&bull;’.

MONOLITHIC

Output only one file including the table of contents. Set by default, but only relevant when the output is not split.

NO_CSS

Do not use CSS; default false. See HTML CSS.

PRE_ABOUT

Used when an About element is output. If set to a text string, this text will appear at the beginning of the About element. If set to a reference on a subroutine, the result of the subroutine call will appear at the beginning of the About element. If not set (the default), default text is used.

PRE_BODY_CLOSE

If set, the given text will appear at the footer of each HTML file; default unset.

PROGRAM_NAME_IN_FOOTER

If set, output the program name and miscellaneous related information in the page footers; default false.

SECTION_NAME_IN_TITLE

If set, when output is split, use the argument of the chapter structuring command (e.g., @chapter or @section) in the <title> instead of the argument to @node.

SHOW_TITLE

If set, output the title at the beginning of the document; default true.

SIMPLE_MENU

If set, use a simple preformatted style for the menu, instead of breaking down the different parts of the menu; default false. See The Parts of a Menu.

If set, links from headings to toc entries are created; default false.

TOP_FILE

This file name may be used for the top-level file. The extension is set appropriately, if necessary. This is used to override the default, and is, in general, only taken into account when output is split, and for HTML.

TOP_NODE_FILE_TARGET

File name used for the Top node in cross-references; default is index.html.

TOP_NODE_UP_URL

A url used for Top node up references; the default is undef, in that case no Top node Up reference is generated. For more about the Top node pointers, see The First Node. For overriding the Up pointer name in case TOP_NODE_UP_URL is set and for other formats, see TOP_NODE_UP in Other Customization Variables.

USE_ACCESSKEY

Use accesskey in cross-references; default true.

USE_ISO

Use entities for doubled single-quote characters (see Inserting Quotation Marks), and ‘---’ and ‘--’ (see General Syntactic Conventions); default true.

Generate <link> elements in the HTML <head> output; default true.

USE_NODE_DIRECTIONS

If true, use nodes to determine where next, up and prev link to in node headers. If false, use sections. If undefined, use USE_NODES value. Default is undefined. Note that this setting does not determine the link string only where the links points to, see xrefautomaticsectiontitle for the link string customization. If nodes and sections are systematically associated, this customization has no practical effect.

USE_REL_REV

Use rel in cross-references; default true.

VERTICAL_HEAD_NAVIGATION

If set, a vertical navigation panel is used; default false.

WORDS_IN_PAGE

When output is split by nodes, specifies the approximate minimum page length at which a navigation panel is placed at the bottom of a page. To avoid ever having the navigation buttons at the bottom of a page, set this to a sufficiently large number. The default is 300.

XREF_USE_FLOAT_LABEL

If set, for the float name in cross-references, use the float label instead of the type followed by the float number (see @float [type][,label]: Floating Material). The default is off.

XREF_USE_NODE_NAME_ARG

Only relevant for cross-reference commands with no cross reference name (second argument). If set to 1, use the node name (first) argument in cross-reference @-commands for the text displayed as the hyperlink. If set to 0, use the node name if USE_NODES is set, otherwise the section name. If set to ‘undef’, use the first argument in preformatted environments, otherwise use the node name or section name depending on USE_NODES. The default is ‘undef’.