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attaching/embedding images

  • 3 cavab
  • 1 has this problem
  • 25 views
  • Last reply by sfhowes

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It seems that I've been stumbling around in the dark for years...

What does "attach" mean when I insert an image? When I send myself an e-mail with an image, I don't see any attached file indicated. The image is embedded.

When I send myself a test with an inserted image, and either click "attach this image" or not, I receive the same e-mail and very very many lines of code (binary?) at the end of the e-mail.

When I check "attach this image" then the message's source has a full web page beginning with HTML and HEAD tags . Then after the closing HTML tag, I get all that code for the image.

But when I want to insert an image and I UNcheck "attach this image" I no longer see HTML in the source. The e-mail is formatted but the source looks like plain text, and that is followed by all that code for the image. But there is no full web page setup beginning and ending with HTML tags.

I thought when I formatted text, it was automatically an HTML e-mail. Clearly, I've never entirely grasped what is going on with HTML mail or with images in e-mails.

Can anyone shed some light on what I'm looking at here? And why would I want to "attach" an image or not? (I'd rather the e-mail display the image rather offering an attached file to open.)

Pros and cons? I'm preparing a small communications campaign so reducing the number of wild cards is more than academic.

I will be truly grateful for any input, Jeanne Thunderbird 78.13.0 (Windows)

It seems that I've been stumbling around in the dark for years... What does "attach" mean when I insert an image? When I send myself an e-mail with an image, I don't see any attached file indicated. The image is embedded. When I send myself a test with an inserted image, and either click "attach this image" or not, I receive the same e-mail and very very many lines of code (binary?) at the end of the e-mail. When I check "attach this image" then the message's source has a full web page beginning with HTML and HEAD tags . Then after the closing HTML tag, I get all that code for the image. But when I want to insert an image and I '''UN'''check "attach this image" I no longer see HTML in the source. The e-mail is formatted but the source looks like plain text, and that is followed by all that code for the image. But there is no full web page setup beginning and ending with HTML tags. I thought when I formatted text, it was automatically an HTML e-mail. Clearly, I've never entirely grasped what is going on with HTML mail or with images in e-mails. Can anyone shed some light on what I'm looking at here? And why would I want to "attach" an image or not? (I'd rather the e-mail display the image rather offering an attached file to open.) Pros and cons? I'm preparing a small communications campaign so reducing the number of wild cards is more than academic. I will be truly grateful for any input, Jeanne Thunderbird 78.13.0 (Windows)

Modified by JeanneR

All Replies (3)

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If the image is on your local computer, it probably doesn't make any difference. If the inserted image is hosted on a remote server, attaching it would make it accessible to the recipient if for some reason they couldn't download it from the remote server, e.g. the message is opened offline or the remote image is removed. There may be other situations where the distinction matters. If you were sending large numbers of messages with remote images, not attaching them might save bandwidth.

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SFHowes

Thanks for your input. I would dearly like to understand it better, but this certainly helps. Makes sense.

I've noticed that on my android phone an e-mail with a "not attached" (embedded?) image displays that image automatically, but an e-mail with an "attached" image does not not display that image (I have to tap an icon). This is far from an exhaustive test, of course. But it's something to consider/explore.

Modified by JeanneR

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Most mobile mail apps will not automatically download image attachments, to reduce data charges or device storage. Some of them will apply the same logic to embedded images, and might or might not have options to control downloads. They generally have fewer settings compared to desktop clients, and choose options that require the least amount of configuration.

But I don't know of any documentation that explains the composed-message attachment options in TB.

Modified by sfhowes