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What's the history behind allowing external images in emails? Was it a size limitation? HTML emails already use only a subset of HTML, so I don't understand wh
by j-james 6y ago
What's the history behind allowing external images in emails? Was it a size limitation?
HTML emails already use only a subset of HTML, so I don't understand why it wasn't trimmed down more to only allow images as data URLs or encoded in Base64.
- JimDabell 6y agoConsider how many HTML emails the average person receives. Now add 2MB+ [0] for all the images that are attached to each of those emails. Then add the 33% overhead for Base64 encoding them. It adds up quickly. Before Gmail came along and drastically increased mailbox sizes, having images attached to every HTML email would quickly overwhelm typical mailboxes. [0] https://www.litmus.com/blog/qa-with-mailcharts-on-email-file-size/ https://www.litmus.com/blog/qa-with-mailcharts-on-email-file...
- peteri 6y agoI suspect partly size but mostly tracking. Images in email have been around since 1992 (RFC341 Multipurpose Internet Mail Extensions https://tools.ietf.org/html/rfc1341 https://tools.ietf.org/html/rfc1341 ) and I don't remember when downloadable images got added to "text/richtext" but the concept of downloadable content is already there in section 7.