Alternatives to Opera Mail for Linux with any license

Thunderbird

Thunderbird is a free, open source, cross-platform e-mail, news and instant messaging client. The project strategy is modeled after Mozilla Firefox.

Free Open Source Mac Windows Linux BSD PortableApps.com ... Haiku
Extensible by Plugins/Extensions Extensible by Plugins/Extensions Built-in RSS reader Calendar integration ... Customizable Extensible by Plugins/Extensions Free API Import from Google Reader Integrated Chat Integrated Web Browser Multiple Account support Export to OPML Import feeds from OPML POP3 Support Portable Tabbed interface Add a feature

1750 Like
- The addons extend Thunderbird's functionality making it by far the best email client ever made. zibusisomasuku • May 2017
Evolution

Evolution is the official personal information manager and workgroup information management tool for GNOME. It combines e-mail, calendar, address book, and task list...

Free Open Source Linux BSD S/MIME GNOME OpenPGP
Built-in RSS reader CalDAV Calendar integration CardDAV ... Encrypted email Integrated Spam Protection Multiple languages POP3 Support Add a feature

150 Like
Claws Mail

Claws Mail is an email client (and news reader), based on GTK+, featuring Quick response Graceful, and sophisticated interface Easy configuration...

Free Open Source Windows Linux BSD
Lightweight Built-in RSS reader Content Filtering Customizable ... Extensible by Plugins/Extensions Support for IMAP Multiple languages Multiple Account support Add a feature

76 Like
- No central inbox or unread box for all mailbox accounts Guest • Oct 2017
Geary

Geary is an email application built for GNOME 3. It allows you to read and send email with a simple, modern interface.

Free Open Source Linux BSD GNOME
No features added Add a feature

69 Like
Sylpheed

Sylpheed is a simple, lightweight but featureful, and easy-to-use e-mail client (mailer, MUA). Sylpheed runs on many systems such as Windows, Linux, BSD, Mac OS X and...

Free Open Source Mac OS X Windows Linux BSD PortableApps.com
Lightweight Add a feature

51 Like
- No central inbox or unread box for all mailboxes in one place. Guest • Oct 2017
Trojitá

Trojitá, is a fast Qt IMAP e-mail client that respects open standards and facilitates modern technologies. Trojitá values vendor-neutrality that IMAP provides...

Free Open Source Windows Linux
IMAP debugging Support for IMAP Add a feature

12 Like
Pantheon Mail

Pantheon Mail is a free open source email client forked by the elementary OS community from Geary...

Free Open Source Linux elementary OS
Multiple Account support Add a feature

7 Like
Mulberry

Mulberry is a powerful, easy to use electronic mail (email) and calendar program that allows you to send, access, and manage email and calendars. Mulberry also helps you...

Free Open Source Mac OS X Windows Linux
CalDAV POP3 Support Sync Calendars Add a feature

6 Like
- Discontinued The project is no longer developed. Last version, 4.0.8, released in February 2007, can be still downloaded from the official website.
- Central inbox tells which account the email is for. Guest • Oct 2017
Hiri

Fast, good looking email client. Lighter than MS Outlook with some unique and clever features. Works ONLY with Outlook / Exchange.

Commercial $ $ $ Mac OS X Windows Linux
Calendar integration Convert Email to Task Add a feature

14 Like
Simple Mail

Simple Mail is a mail client for Firefox. It allows you to get notified, read and write messages for multiple email accounts inside Firefox. Usage: Configure one or...

Free Mac OS X Windows Linux Firefox
No features added Add a feature

5 Like
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