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Conjoon

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Conjoon's own site

What Conjoon is

Conjoon is a free, open-source JavaScript email client with a web frontend. It can manage multiple email accounts in one browser and combine them in a unified inbox. The site lists Google Mail, Microsoft Outlook, AOL, Yahoo, Freenet, GMX and web.de as preconfigured services. Its backend supports IMAP and SMTP through the rest-api-email API, while the webmail package requires a service that complies with that API. The frontend is delivered as static files from a webserver, with official builds available as ZIP downloads. Conjoon can poll mailboxes for new messages and provide sound or desktop notifications; desktop alerts depend on browser permission. A bundled plugin can handle mailto links. The local-mail-account package stores account details in browser Local Storage and sends them with requests. The client is configurable through application and component plugins, and its REST API is documented with OpenAPI. Installation requires Node.js 16 or newer. Building from source requires Sencha Ext JS 7.4 or newer and access to Sencha’s private NPM repository through a commercial SDK license or 30-day framework trial.

Who it suits

Conjoon suits users who want a self-hosted or web-served client for several email accounts. It is also relevant to developers comfortable with its API, backend and build requirements.

What it does well

  • Free open-source web email client
  • Unified inbox for multiple accounts
  • IMAP and SMTP backend support
  • Sound and desktop new-mail notifications
  • Application and component plugin support

What to know first

  • Requires a compatible rest-api-email service
  • Desktop alerts need browser permission
  • Installation requires Node.js 16 or newer
  • Source builds require Sencha Ext JS

Verdict

Conjoon offers a configurable webmail interface with unified multi-account handling and documented APIs. Its self-hosting model and build dependencies make it better suited to technically capable users than to those seeking a ready-made hosted mailbox.

Facts from Conjoon's own pages

Accounts
It can manage multiple email accounts in one browser instance. · conjoon.org, 12 Oct 2026
Account setup
With the local-mail-account package, users can maintain multiple IMAP accounts and account details are stored in browser Local Storage and sent with requests. · conjoon.org, 12 Oct 2026
API
Conjoon documents its REST API using OpenAPI. · conjoon.org, 12 Oct 2026
App coverage
web · conjoon.org, 23 Sept 2026
Backend
The maker describes an installable Lumen/Laravel backend and says the webmail package was developed to work with lumen-app-email. · conjoon.org, 12 Oct 2026
Backend requirement
The webmail package requires a service that complies with the conjoon rest-api-email API. · conjoon.org, 12 Oct 2026
Build dependency
Building from source requires Sencha Ext JS version 7.4 or above, and the guide says access to Sencha's private NPM repository requires a commercial SDK license or a 30-day framework trial registration. · conjoon.org, 12 Oct 2026
Build requirement
Building from source requires Sencha Ext JS version 7.4 or above, and access to Sencha's private NPM repository requires a commercial SDK license or a 30-day framework trial. · conjoon.org, 12 Oct 2026
Deployment
The frontend can be served as static files from a webserver, and official builds are distributed as downloadable ZIP files. · conjoon.org, 12 Oct 2026
Email providers
The site lists Google Mail, Microsoft Outlook, AOL, Yahoo, Freenet, GMX, and web.de as preconfigured email services. · conjoon.org, 12 Oct 2026
Email services
The site says it comes preconfigured for Google Mail, Microsoft Outlook, AOL, Yahoo, Freenet, GMX, and web.de. · conjoon.org, 12 Oct 2026
Extensibility
The client is configurable and extendable, with application and component plugins. · conjoon.org, 12 Oct 2026
Free plan
Yes · conjoon.org, 23 Sept 2026
Hosting
The web client requires a webserver capable of serving static files. · conjoon.org, 12 Oct 2026
mailto links
A bundled plugin can register the client as a handler for mailto links. · conjoon.org, 12 Oct 2026
Multiple accounts
The interface can manage multiple email accounts in one browser instance. · conjoon.org, 12 Oct 2026
New message alerts
The client can poll mailboxes for new messages and provide sound and desktop notifications; desktop alerts require browser notification permission. · conjoon.org, 12 Oct 2026
Product
Conjoon is an open source JavaScript email client with a web frontend. · conjoon.org, 12 Oct 2026
Protocols
Its backend supports IMAP and SMTP operations through the rest-api-email API. · conjoon.org, 12 Oct 2026
Purpose
It is a lightweight, feature-rich email client built for the web. · conjoon.org, 12 Oct 2026
Requirements
The installation guide requires Node.js version 16 or above. · conjoon.org, 12 Oct 2026
Security
The pages reviewed do not state a security certification or compliance standard. · conjoon.org, 12 Oct 2026
Support
The site directs users to GitHub community tools and offers a link to professional support. · conjoon.org, 12 Oct 2026

Where Conjoon stands on Freedom251

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