I really hate Yahoo Mail. The emails don't list in consecutive order. I often reply to an email and my reply is in the middle of a thread.
Make the email normal, like Microsoft Outlook. List the emails individually, at the top or bottom of the thread. It's incredibly frustrating to find emails, and the collapse function sometimes makes this easier, but not always. Let me respond to one, and only one, email, and not be forced to include the entire thread. Very frustrating. I'm probably going to switch over to Google Mail. None of my friends have problems with that.
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