Either the client, add-on or as a stand-alone helper app, what's the best you've found to get rid of dupes ammased over the years?

Not sure how well any dupe finder would work in an email client since emails tend to be threaded and therefore the actual quantity of dupes (in a text comparison) would be very, very low. This is one of those tools that I would be very careful in running and really have a good understanding of the rules at which dupes are being determined.
For Thunderbird, (I actually use Portable Thunderbird), the addon Remove Duplicate Messages.I recall using this in TB, but seems like I had a reason that provoked me to abandon it? Can't remember right now.
You can compare on various things, (see attached), and choose by default which it will delete - although it displays a list afterwards to allow you to manually (de)select emails.
Nice to see you back, Codetrucker
I tried a MapiLabs application a couple of years ago to remove duplicates from my Outlook pst (pretty sure I was running Outlook 2000 at the time). It worked well, but it was as scary as some of the less feature-rich duplicate finders I've tried in that it was hard to determine what I was deleting and from where...
Might be worth a look now, though. I know the MapiLabs add-ins are fairly well thought of. This, of course, assumes that you're using Outlook as your e-mail client...
For Thunderbird, (I actually use Portable Thunderbird), the addon Remove Duplicate Messages.I recall using this in TB, but seems like I had a reason that provoked me to abandon it? Can't remember right now.
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