I've tried to use Thunderbird multiple times over the years, but I always end up with a corrupted mailbox after a week or two, so I go back to Outlook. Is TB finally reliable enough to try again? I'd love to ditch Outlook, but I don't want to be a sucker.
Update: OK, I'm trying it again.
The only issue with "large" mailboxes is that Thunderbird tends to become really slow. But this issue plagues other desktop clients as well.
I would love to find an actually performant email client. It shouldn't take like seconds to sort like 100 000 emails. It's a puny number. The time it takes one can read all the emails from disk a thousand times, it's sad.
On Mac I’ve found MailMate to be excellent in this regard.
I have used Thunderbird for over a decade.
I have never seen any corruption, but if I have threading on, emails get attached to the wrong thread quite often. It's quite annoying.
Thunderbird is my daily driver email client for all my business email for over a decade.
I've never had a single corruption problem in that time, with probably hundreds of thousands of emails. Take that for what its worth.
The only complaint I've ever had is when they redid their UI a year or two ago it got unbearably slow - which improved over the next few iterations until its now fine again.
I have been using Thunderbird myself for years and never had any such problems.
I've used Thunderbird for years and know half a dozen other people using it, including one who has folders with tens of thousands of emails, and have never heard of any data corruption.