# Webmail Client block

> Mail client app shell with folder sidebar, split list and reading panes, and icon app rail

Email workspace: inset Sidebar with account menu, compose dialog, folders, labels and contacts, a search and category-filter message list, a reading pane, and a right icon rail. shadcn Sidebar, Card, Empty, Dialog, ReUI Badge. Mail inbox, webmail UI.

- Type: Pro block
- Category: [App Shell](https://web.dev.reui.io/blocks/application/app-shell.md)
- Page: https://web.dev.reui.io/blocks/application/app-shell/app-shell-20
- Docs (Base UI): https://ui.shadcn.com/docs/components/base/sidebar.md
- Docs (Radix UI): https://ui.shadcn.com/docs/components/radix/sidebar.md
- MCP: `get_block("app-shell-20")`
- Built with: Avatar, Badge, Button, Card, Dialog, Dropdown Menu, Empty, Icon Stack, Input, Label, Scroll Area, Sidebar, Textarea, Tooltip
- Installs with a ReUI Pro or Ultimate license; setup: https://web.dev.reui.io/docs/license-setup

## Best for

A mail layout with a compose dialog, labels and contacts in the sidebar, list and reading panes as empty states and a right shortcut rail

## Agent notes

- No message data ships: `MailList` and `MailView` show `Empty` states where the rows and reading view go, so bring your own
- Replace `MAIL_FOLDERS`, `MAIL_LABELS`, `MAIL_CONTACTS`, `MAIL_CATEGORIES` and `ASIDE_ITEMS` in data.tsx with your own mailboxes and shortcuts
- Send in `ComposeDialog` and Create in `CreateLabelDialog` only call `setOpen`, so nothing is sent or saved

## When not to use

- A message list already filled with sample mail, live search and filter tabs: use [Mail Inbox](https://web.dev.reui.io/blocks/application/app-shell/app-shell-4.md) (`get_block("app-shell-4")`)

## Third-party libraries

- next-themes: [API reference](https://github.com/pacocoursey/next-themes#api), [docs](https://github.com/pacocoursey/next-themes)

## Install

```bash
npx shadcn@latest add @reui/app-shell-20
```

## About App Shell blocks

### When to use

- The outer layout of a multi page product: the navigation around its content area
- Dashboards and admin consoles that switch between workspaces or projects

### When not to use

- One overview page of stats, charts and tables inside your own layout: use the [Dashboard blocks](https://web.dev.reui.io/blocks/application/dashboard.md)
- A top bar on its own, above a page layout you already have: use the [Navbar blocks](https://web.dev.reui.io/blocks/application/navbar.md)

### Agent notes

- Shells that switch themes call `useTheme` from next-themes, so the app must mount the next-themes ThemeProvider

Every ReUI item has a twin like this one; the index is https://web.dev.reui.io/llms.txt. Agents with the ReUI MCP (https://web.dev.reui.io/docs/mcp) get the same guidance from the getters named above.