Re: Why choose plain text over HTML email?
1) Depending on one's group settings, email is by default on groups.ioSpecifically, that would be groups which have chosen the Force HTML option. In other groups an incoming message with only a text/plain body goes out that way.
Gmail, in both the web interface and mobile app, will send a text/plain body (no multipart) if you don't include any formatting as you compose your message (if you are composing a reply, the quoted original message may override this if it has formatting).
2) While it is true that HTML encoding makes the size of the messagePerhaps not always vanishingly (I'm thinking of those email clients that include a bulky CSS header in each outbound formatted message) but in general I concur that images and other files use more space. But at least pictures are generally recognized as worth a thousand words (grin, I couldn't resist that).
I'll do a mea-culpa for the people on limited / metered connections. Though I tend to default to plain text messages, I don't hesitate to switch to HTML when that seems to better suit my content.
I think the bottom line is that, like many things, plain versus HTML has become largely a matter of personal preference, on both the sending and receiving ends. One size doesn't fit all, and fortunately Groups.io doesn't force one or the other on any group.
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