Email, Messaging, & Video Calls > Email How to View the Source of a Message in Mozilla Thunderbird Here's where to find the HTML source code for any email By Heinz Tschabitscher Heinz Tschabitscher Writer University of Vienna A former freelance contributor who has reviewed hundreds of email programs and services since 1997. lifewire's editorial guidelines Updated on November 11, 2021 Tweet Share Email Tweet Share Email Email Yahoo! Mail Gmail What to Know Select the message and go to View > Message Source.Alternatively, highlight the email in your inbox, then go to Menu > View > Message Source.To view an email’s headers, select it and go to Menu > View > Headers > All. Mozilla Thunderbird is a cross-platform, feature-rich free email client with many customization and security options. If you'd like to check out the HTML source code of an email message, Mozilla makes it easy, whether from an unopened or open message. View a Thunderbird Email's Source Information If you'd like to identify a spam message's origins or troubleshoot problems with an email, viewing the message's source can be helpful. Highlight an unread message in your Thunderbird inbox. From the top menu, select View > Message Source. View the message's source information. Quickly view a message's source using a Thunderbird keyboard shortcut. Press Ctrl+U on a Windows or Linux PC, or press Command+U on a Mac. Alternatively, open an email in Thunderbird. From the top menu, select View > Message Source. View the message's source information. View a Message Source With Thunderbird's Menu Button It's also easy to access a message's source using the Thunderbird menu button. Highlight an email in your Thunderbird inbox. Select the Thunderbird Menu button from the upper-right corner. Select View. Select Message Source. View the message's source information. View a Message's Headers If you'd like more information about a message but don't need the source code, opt to view all of a message's headers. Select a message from your Thunderbird inbox. Select View > Headers. Select All. You'll see all the messages' email headers. Was this page helpful? Thanks for letting us know! Get the Latest Tech News Delivered Every Day Email Address Sign up There was an error. Please try again. You're in! Thanks for signing up. There was an error. Please try again. Thank you for signing up! Tell us why! Other Not enough details Hard to understand Submit