rmarkdown 2.14

• Improved highlighting theme arrow regarding accessibility.

• Fixed an issue with site_generator() detection of a site project (thanks, @bhattmaulik, #2344).

• Fixed an issue with Shiny prerendered documents and Pandoc not correctly rendering last Markdown paragraph in HTML (thanks, @gadenbuie, #2336).

• Fixed a bug that site_generator() fails to detect the root dir of the site and causes infinite recursion (thanks, @fisher-j, #2339).

• html_vignette() gains code_folding argument (thanks, @atusy, #2340).

• html_document() can opt-out code_folding = "show" or "hide" for individual code blocks by adding the fold-none class to the code blocks (thanks, @atusy, #2348).

• When using a development version of Pandoc, a .9999 suffix is appended to version number so that pandoc_available() can correctly compared version with last release.

rmarkdown 2.13

• Fix an issue with older R version and vignette building (#2324).

• Fix an issue with older R version and preserve_yaml = TRUE in md_document() (#2325).

• Long title in ioslides_presentation failed to work with Pandoc 2.17.x (thanks, @Am386DX-40, #2327).

rmarkdown 2.12

• html_document() and html_document_base() gains the math_method argument to support all the math rendering engines from Pandoc: "mathjax", "katex", "mathml", "webtex", and "gladtex". For backward compatibility, the mathjax argument still works and will take precedence over math_method, but we recommend using the new math_method argument instead of the mathjax argument, and the latter could be deprecated in the future.

  You can specify a math engine via math_method as an engine name, e.g.,

  output:
    html_document:
      math_method: katex

  or provide both a name and a URL (for mathjax, katex and webtex):

  output:
    html_document:
      math_method: 
        engine: mathjax
        url: https://cdn.jsdelivr.net/npm/mathjax@3/es5/tex-chtml-full.js

  For math_method = "katex", KaTeX CDN will be inserted in version 0.15.2 by default (from jsdelivr). A custom URL toward another CDN can be passed as url.

  For math_method = "webtex", it will default to inset SVG using https://latex.codecogs.com/svg.image?. Use https://latex.codecogs.com/png.image? for PNG. See https://latex.codecogs.com for supported options (dpi, background, ...).

  Most HTML output format using html_document() or html_document_base() as based format should benefit from this new feature.
  See ?rmarkdown::html_document() for details (thanks, @atusy, #1940).

• github_document() also gains the math_method argument set to "webtex" by default so that LaTeX equations can be rendered in the Github Markdown document as images. Previously, LaTeX equations were not rendered. Set math_method = NULL to deactivate.

• Added support for katex R package as a math engine with math_method = "r-katex" in HTML documents. This method offers server-side rendering of all the equations, which means no JS processing is needed in the browser as with usual KaTeX or MathJaX methods. (thanks, @jeroen, #2304).

• anchor_sections can now be easily customized using style or depth element for anchor_sections. For example:

  output:
    html_document:
      anchor_sections:
        style: symbol # use symbol style ("hash", "symbol", "icon")
        depth: 2 # max depth to apply anchor on (default to max which is 6)

  Customizing using a CSS rule is still possible. Detailed explanation and examples have been added to the help page ?html_document.

• Improved the highlighting mechanism in formats that supports highlight argument:

  • It is now possible to pass a custom theme file .theme in highlight argument for customizing the syntax highlighting style used by Pandoc.
  • In addition to Pandoc's own supported themes, two more themes are bundled in the package: highlight: arrow a theme optimized for accessibility and color constrast (thanks to @apreshill), and highlight: rstudio to mimic the RStudio editor theme.
  • For HTML output only, added optional downlit support in html_document() for R syntax highlighting and autolinking. Use highlight_downlit = TRUE to activate it (same argument as in distill). This features require the downlit package.

• Templates for html_document() and ioslides_presentation() gained a new CSS rule to display single line <summary> content inline (rstudio/rstudio#10589).

• md_document() gained a new standalone argument, which is FALSE by default unless toc = TRUE. This allows to output authors, date and other metadata per the Pandoc's template. Due to limitation in how Pandoc is handling metadata blocks in its extensions yaml_metadata_block, preserve_yaml = TRUE now deactivate any extension to let rmarkdown directly handle the keeping of YAML block - this means it does not set standalone = TRUE by default. Meanwhile, github_document() gained the preserve_yaml argument (thanks, @florisvdh, #2297).

• Added available_templates() to list all the templates from a specific package that can be used with rmarkdown::draft().

• Following support in Pandoc 2.15, powerpoint_presentation() gained a incremental argument as other slide formats. As a reminder, setting incremental = TRUE will make lists to display incrementally. See more in Pandoc's MANUAL.

• Added support for Pandoc's dir variable in HTML templates. This is the second Language Variables after lang.

• Added a global option rmarkdown.html_dependency.header_attr (TRUE by default). It can be set to FALSE to opt-out the HTML dependency html_dependency_header_attrs() in documents based on html_document_base() (thanks, @salim-b rstudio/bookdown#865, @maelle r-lib/downlit#1538).

• Rendering using runtime: shiny_prerendered or runtime: shinyrmd now natively supports custom templates. Previously since 2.8, developers had to add a special comment, <!-- HEAD_CONTENT -->, conditionally to shiny-prerendered variable. (See also NEWS from 2.8 for the previous behavior). The new behavior inserts required special comment <!-- HEAD_CONTENT --> as a last element of $header-includes$. If templates rely on the old behavior and require some contents between $header-includes$ and <!-- HEAD_CONTENT -->, consider including them with $header-includes$ (thanks, @atusy, @gadenbuie #2249).

• A shiny prerendered document with only a empty server context does not error anymore. Document will be rendered with a empty server function and server.R file will be ignored. To use server.R, no server context should be present in the Rmd document (thanks, @jcheng5, #2305).

• Fixed a regression with rendering shiny_prerendered document (thanks, @aronatkins, @gadenbuie, #2218).

• Fixed an issue in beamer_presentation() where header-includes would be overwritten by includes = list(in_header =) (thanks, @samcarter, #2294). Same fix as for pdf_document() (#1359).

• Fixed broken links to section headers when number_sections = TRUE is specified in md_document and github_document (thanks, @atusy, #2093).

• draft() now works with devtools::load_all() and testthat when used in other packages.

• Lua Filters: Added two more functions in shared.lua for other package to use:

  • Added type() function backward compatible following Pandoc 2.17 changes.
  • Added print_debug() for easier logging during debug.

rmarkdown 2.11

• Relative paths in parent directories in the css argument of html_document() were incorrectly normalized to absolute paths by #2095 in v2.8. Now relative paths in parent directories will no longer be converted to absolute paths (thanks, @daijiang, yihui/xaringan#331).

• It is possible to specify the version of jQuery via a global option now, e.g., options(rmarkdown.jquery.version = 2) (note that the default major version is 3). This is mainly for advanced users and developers to test different versions of jQuery.

• pandoc_citeproc_convert() now handles correctly bib file containing specific UTF-8 characters on non default UTF-8 systems like Windows (thanks, @mitchelloharawild, #2195).

• Shiny prerendered documents are now pre-rendered in a child environment to avoid allowing the results of static code chunks to exist in the Shiny app environment (@gadenbuie, #2203).

• The previously unexported function convert_ipynb() is exported now (thanks, @acircleda).

rmarkdown 2.10

• md_document() will now handle correctly preserve_yaml value for all variants and all pandoc versions (#2190).

  • with preserve_yaml = TRUE, markdown output will keep the YAML metadata block from the Rmd file.
  • with preserve_yaml = FALSE, markdown output will have no YAML metadata block.

  This fixes a breaking change in Pandoc 2.13 regarding gfm, commonmark and commonmark_x which now supports yaml_metadata_block by default (#2118).

• New supported syntax for Shiny prerendered documents: you can now use server: shiny or server: type: shiny.

• Ability to inject additional functions into Shiny prerendered server scope using the "server-extras" context.

• Fixed the syntax highlighting issue with R's pipe operator |> (thanks, @edzer, rstudio/bookdown#1157).

rmarkdown 2.9

• Fix a regression in version 2.8 when a url is used in css argument (thanks, @vnijs, #2163).

• All HTML dependencies are now correctly supported, included those with only an href component but not file component in their src attribute. Previously, rmarkdown would throw the error 'path for html_dependency not provided' when rendering documents containing HTML dependencies with href components (thanks, @crazycapivara, @matthewstrasiotto, #1805, #1948, #2151).

• Fix an error thrown with output format using a file_scope function (like in bookdown) (thanks, @rfaelens, #2149).

• Fix an issue with copy_ressource = TRUE in html_document_base where very long HTML documents were truncated during post processing (thanks, @oliviermeslin, #2145).

• When run()-ing a runtime: shiny document, an extra temp folder will be used in the output path. With the extra temp random folder in the path, predictable output file names may be used. (#2137)

• When run()-ing a runtime: shiny document with a {bslib} theme, the global theme value wasn't being restored properly. (#2160)

• Floating ToC in html_document can now hide headings with unnumbered and unlisted classes (thanks, @atusy, #1993).

• Fix prefix handling in R Markdown website's navbar for Fontawesome V5 and compatibility with V4. For icon only available in V5, the full prefix + name should be use, especially with new fab prefix (e.g. fab fa-r-project). If no prefix is used (e.g fa-home instead of fas fa-home), the fa prefix will be added for V4 compatibility as it has been deprecated in V5. We advice to use the full prefix + name for icons following Fontawesome documentation. (#1994)

• rmarkdown::site_generator() can hang session waiting for input when the site field is not found in the YAML frontmatter of index.Rmd (thanks, @kevinushey @mirh, #2043).

rmarkdown 2.8

• Fix a issue with Pandoc 2.5 and latex-div.lua - documents can now be rendered as expected without error (thanks, @davidwales, #2121).

• Fix an issue with styling and code folding button behavior when default is code-folding: show. The Button can now be correctly style according to state as aria-expanded attributes is correctly updated. Also, new classes has been added on the button to allow styling during transition: btn-collapsing and btn-expanding are respectively applied during transition Show to Hide and Hide to Show. (This follow Bootstrap behavior for the collapsible block) (thanks, @steveharoz, #2085).

• Fix an issue with citation_package having no effect when using .md file as input to render() with latex and PDF output formats (thanks, @andrewheiss, #2113).

• A new internal option rmarkdown.knit.ext has been added to control the extension of the intermediary knit output during a rendering. It defaults to md to produce *.knit.md. Only useful for very advanced usage (#2098).

• render() won't produce any *.utf8.md intermediary file anymore. This was a leftover from previous versions of rmarkdown. Since knitr 1.24 and rmarkdown 2.0, only UTF-8 input files are allowed. (#2098).

• Fix an Invalid cross-device link error when tempdir() is used for intermediates_dir in render() (thanks, @gorgitko, #2096).

• Fix a regression in HTML default template with floating toc incorrectly placed on small size window (thanks, @grimbough, #2071)

• Provided a runtime: shiny fix for output formats that pass a modified bslib::bs_theme() object to html_document_base()'s theme (thanks, @cpsievert, #2049).

• Rendering using runtime: shiny_prerendered or runtime: shinyrmd will now produce valid HTML by not inserting anymore the full document as body in the resulting shiny apps (thanks, @dakep, #1912). Header content usually containing html dependencies will be inserted in the HTML document at the end of the head before </head>, unless the rendered HTML contains <!-- HEAD_CONTENT --> special comment (see htmltools::renderDocument()). A new Pandoc variable is set in for shiny prerendered document to allow conditional insertion of such content in the the HTML template using $if(shiny-prerendered)$. This has been done in all HTML template in this package. Users of custom template should make this change to provide support for this runtime. See rmarkdown default template (default.html) for an example (#2064).

• Added tectonic as a supported LaTeX engine for generating PDF output (thanks, @dpryan79, #2078). You can specify to use this by adding engine: "tectonic" to your output format in YAML, such as pdf_document.

• When no output_format is provided in any way but an output_file is provided in render(), the default format will be determined based on the extension: "pdf_document" for .pdf, or "word_document" for .docx. Otherwise, it will be "html_document" as previous version (thanks, @pearsonca, #1569).

• Added a new global option rmarkdown.render.message. When set FALSE, render() will not output the message starting by Output created: allowing RStudio IDE to open a preview of the document. This is useful for package developers that would need to emit there own output message for there custom format. See ?render_site for more info on this special message (#2092).

• Internal changes regarding Lua filters. They have now an explicit Pandoc version minimal requirement: A filter will be skipped with a warning printed by the Lua filter if this requirement is not met. For now, all filters work for Pandoc 2.1 and above (thanks, @atusy, #2088). There is also now a new mechanism to have a share Lua filter script loadable by other Lua files: render() will set the RMARKDOWN_LUA_SHARED env var to the path of Lua filter shared.lua so that other filters can access functions defined in it using dofile(os.getenv 'RMARKDOWN_LUA_SHARED'). This is for internal usage only to avoid duplication (thanks, @tarleb, #2103).

• html_document_base gains a css argument, to which html_document's css argument is now passed. This also fix an issue when .sass or .scss files are used with this css argument when self_contained: FALSE. Moreover, sass caching mechanism can now be used when passing .sass or .scss files to the css argument (thanks, @cpsievert, #2095).

• The fig_crop option of PDF document formats (such as pdf_document and beamer_presentation) supports the value "auto" now, which means fig_crop = TRUE when figure cropping tools pdfcrop and ghostscript are available.

• The default value of the fig_crop option of PDF output formats has been changed from TRUE to "auto" (#2077).

• rmarkdown::tufte_handout has been deprecated and will be removed in the future from this package. It has been moved to the tufte package since rmarkdown 0.9.5 (released on 2016-02-22). Please use tufte::tufte_handout instead.

rmarkdown 2.7

• html_document (and html_document_base)'s theme parameter now understands bslib::bs_theme() objects/arguments, meaning that one may opt-into Bootstrap 4 and more easily create custom themes. For examples, see #1706, and for context, see https://rstudio.github.io/bslib/ (thanks, @cpsievert, #1706).

• Files with .scss/.sass extension (i.e., Sass files) provided to html_document's css parameter are now compiled to CSS using the {sass} package. Also, if theme is a {bslib} object, these Sass files may utilize Sass code inside the theme (thanks, @cpsievert, #1706).

• Fix an issue with line numbering in code chunks when .numberlines with Pandoc's highlighting (thanks, @aosavi, #1876).

• Fix an issue with shiny runtime and global.R (thanks, @liaojiahui-r, rstudio/flexdashboard#298).

• Accept latex="{options}", latex=1, or latex=true for Latex Divs.

• Add output_format_filter function to default_site_generator(). Enables custom site generators to customize or even entirely replace the output format right before rendering of each page.

• Automatically exclude renv directory for render_site() (thanks, @jmbuhr, #1996)

• Do not force options(htmltools.preserve.raw = TRUE) when this option has been set, otherwise it is impossible for other packages to turn this option off, e.g., yihui/xaringan#293.

• knitr_options_pdf() will now throw a warning when fig_crop = TRUE but is disabled because required tools pdfcrop and/or ghostscript are missing (thanks, @netique, #2016).

• Eliminated the unnecessary padding in code blocks in the html_document output with Bootstrap 4 themes (thanks, @atusy, #2019).

• github_document() will produce a working TOC even if some headers start with number (#2039).

• Fix an issue with knit_print.data.frame. The ... arguments are no more passed to print() to avoid passing knit_print() arguments options and encoding to custom print() methods (#2047).

rmarkdown 2.6

• Encoding is correctly handled now in html_vignette when checking for identical title and vignette index entry (thanks, @py-b, #1978).

• clean_site() now default to preview = TRUE and will no more remove files without notice. This change will affect the "Clean All" button in the "Build" pane for website project. clean_site(preview = FALSE) must be run to effectively remove files (#1973).

• The intermediate .tex file is now correctly deleted if keep_tex = FALSE when the R Markdown document is not rendered from the working directory (thanks, @vqv, #1308).

• Fix a bug causing certain resources files to be deleted as intermediate files when intermediates_dir is the same as the input (thanks, @bellma-lilly, #1248).

• Fix issues with anchor_sections = TRUE and learnr (thanks, @gadenbuie, #1938).

• Enable use of server.R and global.R alongside runtime: shinyrmd documents.

• pkg_file_lua() now works with devtools::load_all() and testthat when used in other packages.

• Fix pandoc_convert(citeproc = TRUE) not supressing the --natbib or --biblatex options (thanks, @atusy, #1932).

• pandoc-citeproc is now activated if a bibliography field is defined in another YAML block instead of the first YAML block (thanks, @bwiernik, #1364).

• Specify that htmltools::htmlPreserve() should use the pandoc raw attribute
  rather than preservation tokens when pandoc >= v2.0. Note that this option will
  have the intended effect only for versions of htmltools >= 0.5.0.9003.

• anchor_sections in html_documents() now defaults to FALSE. It was introduced in previous version with a default to TRUE, but it is reverted now after hearing feedbacks from the community (thank you!). The # is still used as the character for the anchor but you can easily change that using CSS rules. Examples have been added to the help page ?html_document.

• Using Pandoc's default for --email-obfuscation now. Previously, it was set to none explicitly, which is the default for Pandoc 1.17.2+ anyway. Only users with a Pandoc version before 1.17.2 may see a change in the content of the html source file produced if the document contains email addresses. This change allows to pass the Pandoc's command line flag if you want to set it to another value (thanks,@seankross, #1969).

  output:
    html_document: 
      pandoc_args: ["--email-obfuscation", "javascript"]

  See Pandoc's manual for the meaning of this option.

rmarkdown 2.5

• Tables without header rows (wich can be possible in Pandoc's simple table) are now formatted correctly when using html_document() format (thanks, @fkohrt, #1893).

• html_document gains the anchor_sections argument, which is TRUE by default, so that readers can get links to section headers easily---when you mouse over a section hader, you will see a hash symbol # at the end of the header, which contains the anchor link to this header. You can click on this link and get the URL in the addres bar of your web browser, or right-click on it and copy the URL from the context menu. The hash symbol is defined by the CSS rule a.anchor-section::before {content: '#';}. You can customize it by overriding this rule (e.g., via the css argument of html_document) and use any other symbols or icons, e.g., content: "\02AD8;" (thanks, @atusy, #1884).

• pkg_file_lua() should have thrown an error if the expected Lua file does not exist.

• Provide files_dir and intermediates_dir as attributes on return from render() when run_pandoc = FALSE.

• Supports new Pandoc 2.11 --citeproc flags usage instead of pandoc-citeproc external filter. pandoc_convert() and pandoc_citeproc_convert() will now use the correct flags according to the Pandoc version used. The logic is exported in pandoc_citeproc_args(). See Pandoc release note for more information about the new citeproc processing (#1916).

• Fixed the code highlighting when code block is hidden. Previous version introduced a regression where non default code highlighting was still shown when code_folding is activated and code block is hidden (thanks, @matthewcarlucci, #1921).

• The minimal required version for the xfun package (v0.15) has been specified for R Markdown Notebooks to work properly (thanks, @jmcphers, #1923).

• Fixed a bug in convert_ipynb() when the language is not specified in the .ipynb file (thanks, @acca3003, #1925).

• Introduce runtime: shinyrmd as a more user friendly alias for runtime: shiny_prerendered.