Installation
The current validated baseline is IntelliJ IDEA 2026.2.3, build 262.10968.63. The plugin declares support from that build through the 262 series; other IDE products and builds have not been individually validated. Keep the bundled Markdown plugin enabled. Mermaid diagrams also require the IDE’s JCEF browser.
For a ZIP obtained from the developer, open Settings > Plugins > the gear menu > Install Plugin from Disk, select the plugin ZIP, and restart if prompted. If a manually distributed package uses a self-signed certificate, the IDE may ask you to trust it. Only trust packages and certificates from a known source.
Editing and Raw View
Open a Markdown file in the source editor. Away from the caret, supported markers are hidden and their content is styled. Entering a construct’s source lines or selecting it reveals the syntax for editing. Every caret participates, including additional carets. Multiline constructs reveal their enclosing syntax as needed.
Use Tools > Markdown Ink > Markdown Ink: Live Rendering to switch the current editor between rendering and raw source. The same action is available in the editor context menu and Find Action. Split editors have independent toggles; reopening a file starts with rendering enabled. Raw view removes Markdown Ink’s decorations, not the IDE’s normal Markdown syntax highlighting.
Typing, paste, undo, and redo work on the original document. Copied text includes the original Markdown markers. Styling, caret movement, and the rendering toggle do not change file contents; task activation is an intentional exception.
Supported Syntax
| Construct | Presentation |
|---|---|
| Headings | Six heading levels, including Setext headings; theme-aware colors and subtle level 1/2 rules |
| Emphasis | Bold, italic, strikethrough, and nested combinations |
| Code | Literal inline code and closed fenced blocks, with restrained backgrounds and language labels |
| Links | Inline and resolved reference links, plus angle-bracket URL/email links |
| Lists | Indented bullet and numbered marker columns, preserving original numbers |
| Tasks | Large checked/unchecked boxes with undoable activation |
| Blockquotes | Nested accents and subtle backgrounds, preserving source indentation |
| Tables | GFM alignment, styled headers, inline emphasis, code, and resolved links |
| Mermaid | Closed standalone Mermaid fences rendered locally |
| Math | Supported inline $...$ and standalone $$...$$ formulas |
| Images | Local PNG, JPEG, BMP, and the first frame of GIF images |
| Horizontal rules | Parser-recognized rules rendered as subtle separators |
Links and Tasks
Modifier-click a rendered link using your Go to Declaration mouse shortcut: normally Command-click on macOS or Ctrl-click elsewhere. Alternatively, place the caret in a link and use Markdown Ink: Open Link from Tools, the editor context menu, or Find Action. HTTP/HTTPS and email links open externally; local files and Markdown heading anchors use IDE navigation. Missing targets and unsafe schemes produce an error instead of silently navigating.
Click a rendered task box to toggle it, or use Markdown Ink: Toggle Task at the caret. Multiple carets toggle each distinct task once in a single undoable command. Selections are not bulk task toggles. Assign keyboard shortcuts through the IDE’s Keymap settings. Read-only files and raw view do not activate rendered boxes.
Tables, Diagrams, Math, and Images
Click a table cell to reveal the whole table at its source position. Wide tables use horizontal scrolling; Markdown Ink does not pad or reformat the document. Modifier-clicking a rendered table link follows the usual navigation gesture.
Mermaid rendering uses a bundled library locally, without runtime downloads or a Node installation. Click a diagram, enter its fence, or select it to edit source. Interactive diagram callbacks are disabled. Invalid, incomplete, unsupported, container-prefixed, over-limit, or unavailable JCEF rendering stays readable source.
Math supports common symbols, braced fractions, roots, sums, integrals, accents,
and supported matrix/aligned/cases environments. It uses bundled JLaTeXMath,
without network access or a TeX installation. Unknown commands, macro definitions,
external resources, malformed expressions, and oversized formulas remain source.
Table-cell math, quoted/list display blocks, backslash-delimited formulas, and
math code fences are not rendered.
Images resolve relative to the Markdown file or from absolute/local file: paths.
They fit the editor without upscaling. Relative images in unsaved files have no
base directory and stay source. Missing, invalid, oversized, remote, data-URL,
SVG, HTML, and table-cell images remain source; remote image URLs are not fetched.
Appearance
Open Settings > Editor > Markdown Ink to select Compact or Comfortable density and adjust supported code backgrounds, table striping, image borders, and display widths. Open Settings > Editor > Color Scheme > Markdown Ink for heading, code, link, list, and quote colors. Changes refresh open rendered editors. The editor’s font size and zoom continue to control source text geometry.
Limitations and Troubleshooting
Unsupported syntax remains editable Markdown rather than being removed. HTML, unresolved links, remote images, and constructs exceeding resource limits remain source. Conflicts with native folding can also leave a construct visible.
If rendering is missing, confirm you are in a normal Markdown source editor, the plugin and bundled Markdown plugin are enabled, and Live Rendering is on. Move all carets and selections outside the construct. For Mermaid, confirm JCEF is available. For images, save the Markdown file and check the local path and format. If switching to raw view leaves colors, those may be native Markdown highlighting.
For support, contact support@leoark.com. Include IDE and plugin versions, operating system, and a small Markdown example. Remove private content, file paths, tokens, and credentials before sharing screenshots.