When comparing Mozilla Thunderbird vs MailBird, the Slant community recommends Mozilla Thunderbird for most people. In the question“What are the best e-mail clients for Windows?” Mozilla Thunderbird is ranked 1st while MailBird is ranked 13th.
Ranked in these QuestionsQuestion Ranking
Pro Free (as in freedom and beer)
Pro Lightning Calendar and Address Book integration
Pro Good filtering system
Mozilla Thunderbird offers a flexible filtering system with the ability to set flags and read/unread, as well as sort/assign to new mail directories. There are also numerous plugins available to assist in the filtering.
Pro Consistent and involving a moderate learning curve
The app design of Mozilla Thunderbird has not changed significantly since its beginning, making its learning curve almost non-existent.
Pro Available on Linux, OS X and Windows
Pro Large assortment of plugins available
Mozilla Thunderbird offers a huge amount of extensions to expand the usability and options of the client.
Pro Very reliable
Version after version, Mozilla Thunderbird works as expected.
Pro Tabs for navigation
Pro Send large files easy
Install pCloud plugin for Thunderbird and your files (upto 20 GB free storage included) will be received as download links
Pro Free and paid version
Users who only need to use the basic features of the app have a free version available, though it does limit to only 3 sync'd accounts. There is a paid version that does extend functionality and allows for unlimited account but it does cost $1.00 a month or $45.00 as a one time fee.
Pro You can have multiple accounts
In Pro version, you can create an unlimited number of accounts.
Con Development slowed to only focus on stability and security
Mozilla Thunderbird has slowed down its development of features to only focus resources on security and stability.
Con Subject lines can (temporarily) disappear from the list
This is sporadic behavior.
Con Serious bugs
Clicking on a subject line can bring up the wrong email.
Con Outdated interface
Thunderbird's interface is very outdated and unpleasant. It feels more like a Windows XP application than like a modern MacOS one.
Con Terrible integration with macOS
Simple things - drag/dropping pictures doesn't work, for instance.
Con Drag & drop is impossible
Drag & dropping folders and emails between accounts are not possible.
Con Poor import/export of contacts
You can only import your contacts data via CSV, which isn't the most popular choice. Much more convenient ways to do so exist. Even the older Windows Life Mail program is more flexible when it comes to contacts and offers such features as duplicate checks.
Con Collects user data
Mailbird does collect some user data such as user email addresses, names and client use. So for those that are security minded the use collection of this information may not be wanted and can not be avoided.