I'm still looking for an email client that works.
An email client that can retrieve email, without needing a babysitter.
I've settled for Thunderbird, simply because, with a babysitter, it can retrieve email. That is more than can be said for the other email clients that run on Linux.
Every RFE/bug I submitted was closed "won't fix", because the functionality I was requesting --- which was the ability to retrieve email --- was considered to be something that is not in accordance with their concept of what an email client does.
The Mozilla Foundation seems determined to ensure that Thunderbird remain something other than an email client.
Go to the Thunderbird extensions page, and do a search for extensions that have "Search" as a keyword. "Weave Browser sync", "eBay Auction Search", and "Second Search" are just some Firefox orientated extensions that come up.
