Your question brings up a lot of issues. First, can I change your question around a bit?
1. Can animation cards via email be used to collect e-mail addresses for spammers?
I can state that this is true. The recipient address might be entered at the source site.
2. Can animation cards "leak" information?
Yes. Look up URL MANGLING in which some embedded picture URL can contain "somepicture.jpg?userid=47749660" and that mangled URL just passed that userid back to some server to get the picture. IP addresses are also logged.
In short, html email and animations may have to vanish.
Bob
or both sending the animation card to someone and receiving the animation card ?

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