Plainmark

A free, WYSIWYG Markdown editor for VS Code Desktop and vscode.dev. Obsidian-style live preview — formatting renders inline as you type — without leaving your editor, and without a paywall.

Works everywhere VS Code does

Plainmark runs as a custom editor in both the desktop app and the browser — open the same .md file and get the same live-preview experience in either place.

Features

• Live preview — headings, emphasis, links, lists, blockquotes, and code render inline; the raw Markdown markers reveal only on the line your caret is on.
• Right-click menu — cut/copy/paste plus Format, Paragraph, and Insert: toggle bold/italic/strikethrough/inline code on a selection, turn lines into headings, lists, or quotes, and insert tables, code blocks, math blocks, horizontal rules, and footnotes.
• Tables — visual editing with insert / delete / move row and column, whole-table delete, per-column alignment, and configurable keyboard shortcuts.
• Math — LaTeX rendered with MathJax, inline and block.
• Diagrams — Mermaid flowcharts, sequence diagrams, and more.
• Callouts — Obsidian-style > [!NOTE] admonitions.
• Footnotes, autolinks, images, frontmatter, HTML — full Markdown coverage.
• Paste images — paste a screenshot from the clipboard and Plainmark saves it into your workspace and inserts the image link.
• Paste tables — paste a range copied from Excel, Google Sheets, or a table rendered on a web page and it becomes a Markdown table, bold/links included; tab-separated plain text converts too.
• Paste into quotes — paste multi-line text inside a blockquote or callout and every line gets the > markers it needs, at the right nesting depth, so the whole paste stays quoted.
• Outline view — jump around the document from the Explorer sidebar.
• Word count — the status bar shows a live word count while a Plainmark tab is active.
• CJK-aware — the word count, Ctrl/Alt+Arrow word jumps, and Ctrl/Alt+Backspace word deletion all understand unspaced Chinese and Japanese text.
• Find — press Ctrl/Cmd+F to search the whole document — next/previous, highlight all, and replace — including text scrolled out of view.
• Theming — built-in light/dark themes plus your own CSS.

Your files stay yours

Plainmark's number-one job is to never corrupt your documents. Every edit is provably byte-preserving outside the exact range you change — verified end-to-end (open → edit → save → re-read from disk) and fuzz-tested over hundreds of generated documents, on both the desktop and web builds. It edits your Markdown in place; it never rewrites the parts you didn't touch.

Getting started

1. Install Plainmark from the VS Code Marketplace — or drag the .vsix into VS Code and run Developer: Reload Window.
2. Open any .md or .markdown file and click Open in Plainmark in the editor title bar — or press Ctrl/Cmd+Shift+M.
3. Edit as you would in any WYSIWYG editor. The same shortcut toggles back to the plain-text editor at any time.

Commands

Available from the Command Palette (Ctrl/Cmd+Shift+P):

The two paragraph commands convert a document between blank-line-separated markdown (the conventional style most tools emit) and Plainmark's compact one-line-per-paragraph style. Compact paragraphs joins hard-wrapped lines (without inserting spaces between CJK characters) and removes the blank lines between paragraphs, headings, and lists; Convert to CommonMark does the reverse, producing conventional spacing so every paragraph break survives wherever the file is rendered — including inside blockquotes and callouts, where it writes the quoted blank line (a > on its own line) between paragraphs. Both apply as a single undoable edit and skip anything a rewrite could change the meaning of — hard line breaks, code blocks, tables, list interiors, and 4-space-indented lines (which other renderers read as indented code, a construct Plainmark itself styles as plain text).

Prettify document takes the middle road between those two. It leaves every line break inside a paragraph exactly as you wrote it and only normalizes the blank lines between blocks: one blank above each heading and never one below it, one after a list, quote, table, or HTML block, and none anywhere else — collapsing doubled blank runs along the way. Where dropping a blank would change how the file parses — here or in another renderer — the blank stays (a table below a paragraph, a --- that would turn the line above it into a heading, anything beside a 4-space-indented line). It applies to the whole document as a single undoable edit, and plainmark.prettify.seams lets you re-pin any pair of adjacent blocks to the spacing you prefer.

In the compact style a single line break also ends a quote or callout: a line without the > marker starts a new paragraph below the quote, where conventional markdown would need a blank line and would otherwise fold that line into the quote. Lines that do carry the > marker continue the quote as usual, and list items still absorb their unmarked continuation lines. Convert to CommonMark restores that conventional blank after each quote and callout — nested ones included — so the paragraph below stays outside the quote wherever the file is rendered.

In-table editing shortcuts (insert/move/delete rows and columns, alignment) are configurable via plainmark.tableKeybindings.

Settings

Known limitations

• Paste images requires a saved document and a writable file system; it is unavailable in untitled documents and on read-only workspaces (including some vscode.dev folders).
• Custom CSS (plainmark.styles) accepts local paths and file: URIs only — http(s):// stylesheets and remote @font-face url() are declined.
• Very large documents (above ~2 MB) can make typing sluggish — the whole document stays live-rendered. Plainmark shows a one-time suggestion to reopen such files with the built-in text editor (right-click the editor tab → "Reopen Editor With…").
• Indented (4-space) code blocks are not part of Plainmark's dialect — use fenced ``` blocks. A file that relies on them renders those lines as plain text here while other renderers still show code; Plainmark's editing commands leave the surrounding blank lines untouched, so the file keeps rendering as code everywhere else.

License

MIT