This site will have limited functionality while we undergo maintenance to improve your experience. If an article doesn't solve your issue and you want to ask a question, we have our support community waiting to help you at @FirefoxSupport on Twitter and/r/firefox on Reddit.

Search Support

Avoid support scams. We will never ask you to call or text a phone number or share personal information. Please report suspicious activity using the “Report Abuse” option.

Learn More

HTML outbound message size

  • 6 cavab
  • 1 has this problem
  • 18 views
  • Last reply by 42rhabib

more options

Hello !

I have an issue using thunderbird latest version (78.5.1)

Whenever i'm sending an HTML message the size of the sent messages is way bigger than it should be.

For example, copying an HTML page and sending it using another web client the sent message is 58 KO but using Thunderbird the file size is 140 KO

this is a huge problem as going above 100 KO will make my message be truncated/clipped on some mail client.

I've compared the source file of the message sent from another client and thunderbird and the amount of lines went from 917 on the first one to over 2000 on the thunderbird one

for some reason Thunderbird is adding a lot of useless space on the sent HTML. I've even used an online minifier and while it reduces the original HTML file size by nearly half, it was the exact same size and layout once sent.

I'm also using Quicktext extension to load HTML template but there don't seem to be any difference if I paste the HTML or load it from the extension.

Is there a way to send the HTML mail with the default layout or prevent Thunderbird from adding unneccessary space ? I've tried various methods using the config editor but nothing that solved it so far.

Thank you in advance, and sorry for my broken english (frenchie here) !

Hello ! I have an issue using thunderbird latest version (78.5.1) Whenever i'm sending an HTML message the size of the sent messages is way bigger than it should be. For example, copying an HTML page and sending it using another web client the sent message is 58 KO but using Thunderbird the file size is 140 KO this is a huge problem as going above 100 KO will make my message be truncated/clipped on some mail client. I've compared the source file of the message sent from another client and thunderbird and the amount of lines went from 917 on the first one to over 2000 on the thunderbird one for some reason Thunderbird is adding a lot of useless space on the sent HTML. I've even used an online minifier and while it reduces the original HTML file size by nearly half, it was the exact same size and layout once sent. I'm also using Quicktext extension to load HTML template but there don't seem to be any difference if I paste the HTML or load it from the extension. Is there a way to send the HTML mail with the default layout or prevent Thunderbird from adding unneccessary space ? I've tried various methods using the config editor but nothing that solved it so far. Thank you in advance, and sorry for my broken english (frenchie here) !
Attached screenshots

Chosen solution

I do not see any 'unnecessary' space. There are at least five tables in that email that show a close and loads of 'div' that need closing.

When you 'copy and paste' all the formatting that was previously included in the original MS created email, it will look completely bloated.

Recreate the email in Thunderbird and save it as a template and it will only include what is necessary for the email and it will be a lot smaller.

It's almost as if someone originally created it to be posted in a webpage.

Read this answer in context 👍 0

All Replies (6)

more options

You picture shows an msoNormal tag, which suggests it's been composed with Outlook or Word. Are you composing in Word and then copying into a TB Write window?

more options

I did extract the source of the HTML from Outlook yes.

but it was a mail sent from GMAIL so not exactly "composed" in outlook. (I think)

more options

Was it composed in gmail webamail, or composed in a gmail account set up in Outlook? I think you will always find that MS software adds significant formatting to html mail, no matter which client is used. Compare the size of an html message composed in Outlook with that of an identical message composed in TB.

more options

Well the original HTML file cas composed externally using some Adobe software, but the result was sent to my account using Gmail.

I don't get why I can send it with literally any mail tool and Thunderbird is the only one that increase the file size by twice the original value.

Maybe if I could share you the original HTML code you might figure it out but I can't share it here.

more options

Seçilmiş Həll

I do not see any 'unnecessary' space. There are at least five tables in that email that show a close and loads of 'div' that need closing.

When you 'copy and paste' all the formatting that was previously included in the original MS created email, it will look completely bloated.

Recreate the email in Thunderbird and save it as a template and it will only include what is necessary for the email and it will be a lot smaller.

It's almost as if someone originally created it to be posted in a webpage.

more options

I ended up recreating the whole template on Thunderbird like you stated and it's working like it should.

thanks