Settings
Open the settings panel with Folio → Settings… on macOS or File → Settings… on Windows and Linux (⌘, / Ctrl+,), or with the gear at the start of the status bar. It has the appearance, document style, reading width, font size, the sidebar and the outline. In the desktop app it also has the workspace folder, skipped folders, scan depth, your editor, custom CSS, review notes and coding agents.
settings.json
The desktop app keeps its settings in settings.json. Open settings.json at the foot of the settings panel opens it. Folio applies a change as soon as you save the file.
| Platform | Folder |
|---|---|
| macOS | ~/Library/Application Support/Folio/ |
| Windows | %APPDATA%\Folio\ |
| Linux | ~/.config/Folio/ |
{
"workspace": "/Users/me/notes",
"skipDirs": [".git", "node_modules", ".venv", "…"],
"maxDepth": null,
"theme": "system",
"editor": null,
"reviewIntroOn": true,
"reviewIntro": ""
}| Setting | What it does |
|---|---|
workspace | The folder Folio opens. |
skipDirs | Folder names skipped wherever they appear. |
maxDepth | How many folder levels below the workspace are scanned: docs/guide.md is depth 1. null scans every level. |
theme | "system", "light" or "dark". The ◐ menu sets the same value. |
editor | The editor for Open in Editor. On macOS, an app name such as "Visual Studio Code" or "Cursor"; on Windows and Linux, a command on the PATH, such as "code". |
reviewIntroOn, reviewIntro | Settings → Review notes: whether review notes start with instructions for the agent, and their wording. "" uses the default; {documents} stands for the file name or "3 documents". Folio's MCP server reads them too. |
Skipped folders
The default skipDirs covers version control, dependencies, virtual environments, caches and tool data: .git, node_modules, .venv, venv, __pycache__, .cache, .local, .tox, .nox, .mypy_cache, .pytest_cache, .ruff_cache, .next, .nuxt, .svelte-kit, .yarn, bower_components, .terraform, Pods and .gradle.
It leaves out dist, build, vendor and target, because some projects keep real documentation there. Add them if yours don't.
Your editor
With editor left at null, macOS uses the first of these that's installed: Visual Studio Code, Cursor, Zed, Windsurf, Sublime Text, BBEdit, Nova, Typora, iA Writer and MarkText. Otherwise it uses the default text editor. Windows and Linux use the default app for Markdown files.
Custom CSS
In the desktop app, View → Edit Custom CSS… opens custom.css in your editor. Folio creates it from a commented template the first time. It applies on top of the chosen document style, and changes show as soon as you save. Target the document with .folio-document; to change only one style, use [data-doc-style="book"] .folio-document (or default, compact).
What Folio remembers
Between launches, the desktop app remembers the window's size and position, and how you left the view: the sidebar's width, the folder tree and which folders are open, the outline, reading width, font size and the full-text search toggle. These files sit beside settings.json and aren't meant to be edited by hand.
The live demo remembers the appearance, reading width and font size in your browser.