ContainerCookies

demo.mp4

A Firefox extension for viewing and managing cookies per container.

Features

• Select any Firefox container (or "No container") from a dropdown
• Browse cookies grouped by domain
• Expand a domain to see individual cookie names and values
• Delete a single cookie or all cookies for a domain
• Clear all cookies in the selected container at once
• Search by domain or cookie name
• Copy cookies as JSON at three granularities, or copy a single name/value with one click — see Copying
• Two-click confirmation for every destructive action, so no accidental wipes — see Usage

Copying

You can copy cookies at four levels of granularity. All multi-cookie exports use the same JSON shape, so they're easy to feed into scripts.

Action	Where	Format
Copy every cookie in the container	copy button in the toolbar	JSON array of {domain, cookies} entries, sorted by domain
Copy every cookie of one domain	📋 copy next to a domain header	JSON object: {domain, cookies: [{name, value}, ...]}
Copy one cookie (as JSON)	copy next to the cookie	JSON object: {domain, cookies: [{name, value}]}
Copy the cookie name	click the name in the list	plain string
Copy the cookie value	click the value in the list	plain string

Examples

Copy a single cookie — the resulting clipboard contents:

{
  "domain": "example.com",
  "cookies": [
    { "name": "session_id", "value": "abc123def456" }
  ]
}

Copy all cookies of one domain:

{
  "domain": "example.com",
  "cookies": [
    { "name": "session_id", "value": "abc123def456" },
    { "name": "theme", "value": "dark" }
  ]
}

Copy every cookie in a container (entries are sorted alphabetically by domain):

[
  {
    "domain": "example.com",
    "cookies": [
      { "name": "session_id", "value": "abc123def456" }
    ]
  },
  {
    "domain": "other.com",
    "cookies": [
      { "name": "preference", "value": "compact" }
    ]
  }
]

Tip: piping the container export into jq lets you extract one cookie's value across every domain that has one:

cat container.json | jq '[.[] | .cookies[] | select(.name=="session_id") | .value]'

Installation

From addons.mozilla.org

https://addons.mozilla.org/en-US/firefox/addon/containercookies/

Temporary (development)

1. Open Firefox and go to about:debugging
2. Click This Firefox
3. Click Load Temporary Add-on
4. Select manifest.json from this folder

Note for Flatpak Firefox users: unzip the extension into your home directory (~/) first — Flatpak sandboxing prevents loading extensions from /run/user/... paths.

Requirements

ContainerCookies requires Firefox Multi-Account Containers to display container names and colors. Without it, only the "No container" option will be available in the dropdown.

Usage

1. Open a few websites in different containers
2. Click the ContainerCookies icon in the toolbar
3. Select a container from the dropdown to see its cookies
4. Expand any domain to browse individual cookies
5. Copy with the buttons described in Copying; click a cookie name or value to copy just that piece of text
6. Delete with confidence: the first click on a delete button arms it (turns red, 3-second countdown). Click again within the window to actually delete. This two-click pattern applies to single cookies, whole domains, and the "Clear all" button in the toolbar — no accidental wipes.

No account or external service required — everything runs locally in your browser.

Changelog

See CHANGELOG.md for the full version history.

License

Copyright (C) 2026 soko1 me@cryptopunks.org

This program is free software: you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation, either version 3 of the License, or (at your option) any later version.

This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details.

https://www.gnu.org/licenses/gpl-3.0.html