Folio

Appearance

FAQ ​

Does Folio change my files? ​

No. Folio only reads your documents. Highlights, notes and bookmarks are kept in Folio's own folder: ~/.folio, or %USERPROFILE%\.folio on Windows.

What happens to my marks when a document is edited? ​

They follow the text. If the passage a highlight was on is deleted, the highlight is shown as not found in the Marks view, where you can remove it.

Is Folio free? ​

Yes. Folio is free and open source under the MIT License.

Does Folio work offline? ​

Yes. Rendering, search, math, Mermaid diagrams and your marks all work without a connection. Folio only goes online for two things:

  • Updates. Shortly after launch, and every few hours, Folio checks GitHub Releases for a new version and downloads it in the background. You're asked to restart when it's ready, or it installs the next time you quit. Without a connection, the check just fails quietly.
  • Web images. An image in a document with an https:// address is loaded from the web, as in any Markdown viewer. Images from your own folders don't need a connection.

Links to websites open in your browser. Folio has no account, and sends no analytics or usage data.

Can I use it with an Obsidian vault? ​

Yes. Open the vault folder. Wiki links, image embeds and front matter work as they do in Obsidian. See Markdown support.

Can I share my marks with someone else? ​

Not directly. Folio has no sync or shared workspace: your marks stay on your computer. To share a review, send your notes as text:

  1. Open the Send dialog with the header's clipboard button, or press ⇧⌘C / Ctrl+Shift+C to copy the unsent notes straight away.
  2. Paste the text wherever the review happens: a pull request comment, an issue, a chat message or a coding agent.

The text is Markdown. Each note comes with its quoted passage, section, file path and line, so it still makes sense to someone who isn't using Folio. Notes marked Only me and highlights without a note are left out. See Reviewing specs with a coding agent.

The marks files in ~/.folio/marks are JSON, one per document, but they're keyed by each document's full path on your computer. They aren't meant to be copied to someone else's computer.

How do I back up my marks? ​

Back up the ~/.folio folder (%USERPROFILE%\.folio on Windows). It holds all your highlights, notes and bookmarks, for every folder you've opened.

Where do I report a bug or ask for a feature? ​

On GitHub Issues.