As described in this thread.
Digital (formerly modedeep) said that emoji are not quoted when using the quote command popup, but I noticed the same thing happening if I select some text with an emoji and quote it with the Reply link.
Possibly isolated to Webkit derivatives, I've had no problems with this on Firefox. It only occurs on Chrome (and reports of Safari doing the same).
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Possibly isolated to Webkit derivatives, I've had no problems with this on Firefox. It only occurs on Chrome (and reports of Safari doing the same).