Because Qualcomm stopped development over a decade ago certain features are problematic these days, certificates updates and the lack of a decent HTML editor for example.
That means that I also have to use Mozilla's Thunderbird for some jobs.
Let me say this categorically: Thunderbird isn't in the race with Eudora. It would take chapters for me to do a proper comparison and show you how truly bad Thunderbird is by comparison. If Thunderbird or any other open source client is ever to catch up with Eudora then a huge amount of work will need to be done.
There is one thing I've never understood about classic well designed software and that is why are supposed clones such as Thunderbird so inferior to the original. One would think Thunderbird's designers would simply copy the Eudora paradigm and correct its out of date features on the way.
Well it's not so with Thunderbird. Perhaps someone knows the reason why.
Anyway, Eudora is on my machine to stay for the time being. It'll be there until the POP/IMAP protocol ceases to work!