Cloudmagic HTML signatures have broken images in thunderbird, how to fix?
I am using cloudmagic for email on my phone and utilizing the html signature functionality.
The signature displays fine in outlook, outlook.com, gmail and so on however in thunderbird all images are broken and do not display.
How do I fix this?
Chosen solution
Is the image included in a standards compliant form?
email does not use file extensions to identify a file as a "type" it uses the mime type.
Microsoft apparently think everyone should do it their way and use file extensions. This is actually a very bad idea as it makes including phishing attacks and malware so much easier. But they are the 1000 ton elephant in the room.
So open the message source. ((ctrl+U)
images will appear looking like this.
Content-Type: image/png; name="Grates.PNG" Content-Transfer-Encoding: base64 Content-Disposition: inline; filename="Grates.PNG"
The important part of this is the ContentType which tells Thunderbird what the item is. Lots of non compliant products use octet stream or other generic statements meaning "binary data" what are your email showing in there?
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Chosen Solution
Is the image included in a standards compliant form?
email does not use file extensions to identify a file as a "type" it uses the mime type.
Microsoft apparently think everyone should do it their way and use file extensions. This is actually a very bad idea as it makes including phishing attacks and malware so much easier. But they are the 1000 ton elephant in the room.
So open the message source. ((ctrl+U)
images will appear looking like this.
Content-Type: image/png; name="Grates.PNG" Content-Transfer-Encoding: base64 Content-Disposition: inline; filename="Grates.PNG"
The important part of this is the ContentType which tells Thunderbird what the item is. Lots of non compliant products use octet stream or other generic statements meaning "binary data" what are your email showing in there?
Its using octet stream as you suspected.
That will be that then.
Thank you for the response.