If your concerns are just the headers, we probably can find other solutions. I feel the API should guarantee to produce valid emails and if the developer needs to prepare the actual message string, I see a lot of things that can go wrong. Encoding being one of the most prominent one.
Bug 1545930 Comment 26 Edit History
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If your concerns are just the headers, we probably can find other solutions. I feel the API should guarantee to produce valid emails and if the developer needs to prepare the actual message string, I see a lot of things that can go wrong. Encoding being the most prominent one.