Neo

An AI chat sidebar for Firefox that runs on your own API key.

JavaScriptWebExtensionsFirefoxManifest V3HTMLCSS
Source on GitHub

Project overview

Neo is a Firefox extension that puts an AI chat in the sidebar or in a compact popup. Requests go straight from the browser to the provider the user configures: any OpenAI-compatible endpoint, DeepSeek or Anthropic. Open tabs and screenshots of the visible page can be attached to a message, and answers stream in as sanitized Markdown. There is no server and no account; settings and conversations stay in the extension's local storage. It is written in plain HTML, CSS and JavaScript with no framework or build step.

What it does

Bring your own AI

  • OpenAI-compatible endpoints, DeepSeek and Anthropic
  • Local models through Ollama or LM Studio

Context from the browser

  • Attach an open tab's title, URL and page text
  • Screenshots of the visible page for vision models

Local by design

  • No server or account; chats stay in Firefox
  • Pages and screenshots are only read on request

Inside the project

Screenshots of Neo running as a temporary add-on in Firefox 159, captured on 29 October 2026. The replies come from a local mock of an OpenAI-compatible endpoint with scripted answers, so no real model or API key was used.

Asking about an open tab

Asking about an open tab

The GitHub tab attached with 馃搫 and a streamed Markdown answer in the sidebar

 Screenshot of the visible page

Screenshot of the visible page

A screenshot of the current tab sent to a vision-capable model

 Tab picker

Tab picker

Choosing which open tab to attach to the next message

 Conversation list

Conversation list

Several chats, stored locally in Firefox

 Provider settings

Provider settings

Settings filled in for a local Ollama model

Technologies & implementation

Technology stack

  • JavaScript 路 HTML 路 CSS, no build step
  • Firefox WebExtensions 路 Manifest V3
  • Sidebar, popup and context-menu APIs
  • Server-Sent Events streaming
  • OpenAI Chat Completions 路 Anthropic Messages API
  • web-ext 路 Python / Pillow icon generator