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Thunderbird Making HTML E-mail Larger than other Apps

  • 1 reply
  • 1 has this problem
  • 17 views
  • Last reply by Matt

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Hi All,

I hope someone can help with this. I've recently developed a HTML Template for an e-mail newsletter which is sent via mailmerge using Thunderbird. The HTML Template doesn't attach images to the e-mail when it's sent, so the images are hosted on an existing website.

When I send the HTML Template using Thunderbird, the file size is over 200kb - which is a problem given Gmail cuts off sections of e-mails which are over 102kb in size.

What's stranger is that when we input the same HTML Template and send as an e-mail via Gmail or even a basic webmail app like Roundcube (cPanel) - the e-mail size is more like 60kb to 80kb.

I've even tried sending the e-mail from Gmail to Thunderbird (which arrives at around 60kb), and then sending that same e-mail from Thunderbird, which then increases the size to around 160kb.

We've tried sending the e-mail individually from Thunderbird and using the mailmerge extension, and in both cases, the size of the e-mail is much larger than when the same code is sent from a different e-mail provider.

Is there something about Thunderbird which is causing this to happen!?

Many thanks for any help!

Hi All, I hope someone can help with this. I've recently developed a HTML Template for an e-mail newsletter which is sent via mailmerge using Thunderbird. The HTML Template doesn't attach images to the e-mail when it's sent, so the images are hosted on an existing website. When I send the HTML Template using Thunderbird, the file size is over 200kb - which is a problem given Gmail cuts off sections of e-mails which are over 102kb in size. What's stranger is that when we input the same HTML Template and send as an e-mail via Gmail or even a basic webmail app like Roundcube (cPanel) - the e-mail size is more like 60kb to 80kb. I've even tried sending the e-mail from Gmail to Thunderbird (which arrives at around 60kb), and then sending that same e-mail from Thunderbird, which then increases the size to around 160kb. We've tried sending the e-mail individually from Thunderbird and using the mailmerge extension, and in both cases, the size of the e-mail is much larger than when the same code is sent from a different e-mail provider. Is there something about Thunderbird which is causing this to happen!? Many thanks for any help!

All Replies (1)

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My guess is Thunderbird is sending both an HTML and a text version. It is the default action. This is what would be considered responsible, and removed those stupid "click here to see the email" when the mail client can only display text. However if you are sending bulk email use a mailing house not a mail client. The Thunderbird project used mailchimp for those services to the project, but that is not a recommendation, simply a notation of fact. The project does not use Thunderbird for bulk mailing.