
Mail Data Loss in macOS 10.15 - zdw
https://mjtsai.com/blog/2019/10/11/mail-data-loss-in-macos-10-15/
======
herpderperator
I always find it strange when OS updates affect apps in this way. It just
shouldn't happen. It reminds me of when Linus preaches that "the kernel should
never break userspace". Why would a OS update suddenly cause the _Mail_ app --
developed by the _same_ company as the OS, for what it's worth -- to have
these strange (and catastrophic) data syncing issues?

And, just to add, I am tired of OS updates updating and/or releasing userspace
things like "Music" and saying:

> iTunes forever changed the way people experienced music, movies, TV shows,
> and podcasts. It all changes again with three all-new, dedicated apps —
> Apple Music, Apple TV, and Apple Podcasts — each designed from the ground up
> to be the best way to enjoy entertainment on your Mac. [0]

It is literally the FIRST thing they advertise. What does that have to do with
the OS? Nothing! They should release apps separately from major OS versions.

[0]
[https://www.apple.com/macos/catalina/](https://www.apple.com/macos/catalina/)

~~~
yjftsjthsd-h
> I always find it strange when OS updates affect apps in this way. It just
> shouldn't happen.

Right? Are there not automated tests for this stuff? I would expect that if
you commit something that causes this, the next day you get an email that
says, "your name is on commit $FOO, which caused regression tests to fail in
tests/firstparty/apps/mail; please fix it (sincerely, Jenkins)" or so. Heck,
it's more egregious here because it's a first party application, but it seems
like it would be in their interest to keep copies of the most popular third-
party applications and include those in their test suites as well. ("Hi,
Adobe? Hey, it's Apple. Hey, so this is a heads up that Photoshop doesn't work
with the new OS version; we're sending you a RCA so you can fix it before it
hits end users.")

~~~
userbinator
I wouldn't place much emphasis on testing, and Apple most likely has tests,
because the exact conditions that trigger such bugs are often so narrow that
an artificial testing environment for them to "make the stars line up" would
be nearly impossible to create. Anything involving multithreading/asynchronous
code tends to fall in that category, but even single-threaded code can be like
that; to make an artificial relevant example, it could be something like "if
two consecutively received emails are exactly 8192 bytes long[1], and the
first one is the 256th message in the folder when sorted by the sender's
email, then the second one will be missing." That's a condition which you're
highly unlikely to hit, even more so if you're generating test data randomly
(as some tools like to do, and fuzzing is one prominent example). Even if you
specifically test power-of-2 sizes, the two-in-a-row subcondition would make
that improbable. If you let everyone in Apple "dogfood" the software, they
might not hit. Yet everyone who has subscribed to a set of mailing lists that
happened to issue such an exact sequence of messages would see the bug.

That's also why I think other automated tools and "code quality" metrics don't
help so much; tests are more of a sanity/last-chance check and shouldn't be
relied upon to catch everything. Correctness should be assured through design
and code reviews, and for that nothing beats the power of intense mental
deliberation. To paraphrase a popular saying, "there is no replacement for
intelligence."

[1]
[https://news.ycombinator.com/item?id=8797640](https://news.ycombinator.com/item?id=8797640)

~~~
fauigerzigerk
You are absolutely right, but all of this is known to Apple.

What they need to do when it's potentially about permanent loss of user data
is to prove that a postcondition is met (i.e. all messages were successfully
converted) and roll back if it isn't.

Instead they apparently sync the faulty data with the IMAP server and destroy
what most users consider their email backup. This is breathtaking incompetence
and negligence if it's actually true.

The worst thing is that it is near impossible to find out whether or not
you're affected by this.

I'm so fed up with Apple and its second rate software. I have lost music
playlists in this ill fated Catalina "upgrade" as well. I've been wanting to
move on to a more flexible and less oppressive environment for a while. At
least this finally breaks my inertia.

~~~
coldtea
> _I 'm so fed up with Apple and its second rate software. I have lost music
> playlists in this ill fated Catalina "upgrade" as well. I've been wanting to
> move on to a more flexible and less oppressive environment for a while. At
> least this finally breaks my inertia._

Try Linux or Windows! Their first rate apps will keep your email safe and
secure!

[https://bugs.launchpad.net/ubuntu/+source/evolution/+bug/372...](https://bugs.launchpad.net/ubuntu/+source/evolution/+bug/37227)

[https://forums.linuxmint.com/viewtopic.php?t=88648](https://forums.linuxmint.com/viewtopic.php?t=88648)

[https://blog.lightlyseared.online/2010/04/06/fixing-
corrupt-...](https://blog.lightlyseared.online/2010/04/06/fixing-corrupt-mail-
folders-in-evolution/)

[https://windowsreport.com/outlook-emails-
disappeared/](https://windowsreport.com/outlook-emails-disappeared/)

[https://thenextweb.com/microsoft/2013/06/20/outlook-coms-
mis...](https://thenextweb.com/microsoft/2013/06/20/outlook-coms-missing-
email-bug-resurfaces-as-users-report-deleted-inboxes-gaps-and-other-issues/)

[https://www.pcworld.com/article/237103/five_outlook_nightmar...](https://www.pcworld.com/article/237103/five_outlook_nightmares_and_how_to_fix_them_.html)

~~~
fauigerzigerk
You're missing the point. If I'm getting shoddy QA anyway, why keep paying
Apple's excessive prices and accept their oppressive content restrictions?

~~~
coldtea
No reason, especially since others are both cheaper AND better at shoddy QA!

------
thelittleone
The position of Apple today reminds me a lot of Microsoft after they peaked
(~2000?). Cocky to the point of arrogance because of market position, past
innovations and brand loyalty (e.g., it is cool to own Apple). But loyalty and
market sentiment can only endure so much amidst plummeting product quality,
nonsensical pricing (e.g. dongles) and lack of any meaningful innovation
(thinner doesn't count). Apple doesn't listen because they think they know
better (and that used to be true).

\- Peaked in terms of brand perception rather than market cap or market share.

~~~
fastball
It wasn't obvious at the time, but I think in retrospect the case can be made
that Apple's ability to innovate effectively (both in terms of time and
quality) died with Jobs.

Jony Ive made a good effort to keep pushing hardware design forward, but
without Jobs to curb his worst impulses (in my opinion), the end was result
was "thinner above all else" (as you mention).

If someone can come up with a corporate structure that allows for the dynamism
provided by having a visionary dictator at the helm, _without actually needing
a visionary dictator_ , that would be a corporate structure that would take
the world by storm.

~~~
sha90
> It wasn't obvious at the time, but I think in retrospect the case can be
> made that Apple's ability to innovate effectively (both in terms of time and
> quality) died with Jobs.

Oh stop. Apple's effectiveness was entirely a product of its time. You had
designers building the Zune and calling it competitive but really there was no
competition for the products Apple was building for a market that was
screaming for a better balance of form vs function.

This picture of Apple's innovation includes no part of OSX, which was always
an OS that was technically capable but superbly messy and extremely behind on
the times.

Innovate effectively? For a long time of Jobs' tenure, Cocoa was being
supported on BOTH Objective-C and Java, and when they ripped it out, they
actually chose Objective-C, not Java, as their platform of choice (in
retrospect: wow), only to have to build yet another platform (Swift) just a
few years later (Swift of course, based off of MacRuby, which they initially
tried to build Cocoa on top of internally, so I hear).

Innovate maybe, but effectively no. There is a whole host of broken,
abandoned, and outright bad decisionmaking in the OS layer at Apple. Apple's
success has everything to do with their success with industrial design, UX
design & marketing, and just a bit of being at the right place at the right
time.

IMO this interpretation fits the timeline much more cleanly: Apple was
churning out the same iPhones and Macbooks long before Jobs left, just as they
had been before with the iPod. The butterfly switches, the thin above all
else, that's all part of Apple's MO dating back years. Lack of FM radio on the
iPods, lack of IR sensors on their early phones, removal of removable
batteries, headphone jacks, USB-A, etc, is all part of the DNA. A $5000 screen
is not surprising to anyone who saw the Powermacs of the last generation.
Butterfly switches look an awful lot like bendy iPhones, which look an awful
lot like DOA Powerbooks.

I'm really not sure what part of this is new post-Jobs, but I have a good
feeling this is a great case study of confirmation bias. If you believe Jobs
was a one-of-a-kind irreplaceable visionary who was single handedly
responsible for Apple's success, then you have no choice but to interpret any
action Apple makes post-visionary as a failure, otherwise you were wrong about
the one-of-a-kind irreplaceable visionary.

And it would be a pretty big blow to most to be wrong about Steve Jobs.

The other interpretation, of course, is that Jobs was not a magical visionary,
just a smart guy who made a couple of right decisions, got lucky on lots of
others, while still getting it wrong on plenty of occasionss (Macintosh TV
_cough_ Apple TV _cough_ Apple TV2), just like most fallible humans.

~~~
pjmlp
Apple only kept Java around because coming from Pascal and C++ background they
were unsure how the Apple developer community would welcome Objective-C.

When they saw the community had no issue embracing Objective-C that is when
they dropped the Java bridge, QT for Java and eventually their own JVM.

Chris Lattner never speaks about MacRuby on his interviews, rather how, like
clang before it, Swift started as a side project before being shown to upper
management.

According to his interviews, many of the Objective-C 2.0 and later
improvements were already a kind of slow roadmap into Swift.

~~~
apple4ever
Yeah, but Objective-C 3.0 would have been a much better path than Swift. It
would have allowed easier upgrading to existing code instead of mass rewrites,
which always bring their own bugs (and that's ignoring the bugs in Swift
itself).

------
quadrifoliate
A lot of this is a repeat of weird issues that we saw 8(!) years ago with OSX
Lion. Perhaps I'm off the mark here, but I strongly suspect there's lack of a
proper _manual_ QA team at Apple.

QA at most so-called "modern" companies these days has turned into overly
fetishising automated testing. Automation is valuable, but crucially also
leads to situations where the least-common-denominator situations get tested
since it's easier to automate the conditions for testing them. So for example
you might write an automated test that verifies that the mail _index_ is
correctly upgraded from (say) El Capitan to Mojave to Catalina; but that
doesn't show the whole picture. There could be 20 other complex factors that
affect it when it's used as part of an OS upgrade, and none of those get
tested.

Project managers, line managers, and other suits also seem to love automated
testing, because you can show off some kind of real number to someone in an
"Oh we wrote 200 tests this cycle, isn't it great that we can run them
everyday" way, even if there are 0 issues found. Manual testing in the same
case leaves you with no output that can be run in an automated fashion. Also,
no one wants to argue _against_ automation (even if it's taking away manual
testing resources) because that can make you seem old-school and out of touch.
And once this attitude gains steam, no one on the QA team will want to go
against the grain and say "You know what, we should spend more time _not_
writing automated tests".

All of this is to say -- sometimes during testing, you simply have to put
yourself in a user's place (for as many different kinds of user you can
imagine) and actually _use_ the thing you're supposed to be testing. I
strongly suspect that Apple is not investing enough, or at all in this kind of
testing. Instead, they are pushing it off to those enthusiasts who install and
use beta or newly released versions of their software. So far, this strategy
seems to have paid off for them, but perhaps people will wise up and stop
testing their stuff for free. I am certainly not upgrading my machines to
Catalina any time soon.

~~~
userbinator
_Also, no one wants to argue against automation (even if it 's taking away
manual testing resources) because that can make you seem old-school and out of
touch._

As someone who is "old-school" and has argued against automation countless
times, it's more that your arguments against it will likely be dismissed
because the management just wants to see the numbers on their pretty "quality
metrics" dashboards going up; regardless of what it means for the actual
quality of the product. They'll even ask you to "fix" automated tests by
forcing them to pass, if they are failing for some reason you don't know yet.
Truly a case of "you get what you measure". It's only when you start showing
them the bugs that customers come back with and why they couldn't possibly be
discovered in automated testing (at least without an impossibly large and
nearly-infinite set of test cases on a similarly large set of hardware and
software) that they may start to listen to you. Sometimes.

~~~
sooheon
When they’re ready to listen, what do you propose instead?

------
reaperducer
I wish I only lost mail data in the upgrade to Catalina.

I lost 400GB of data when the installer repartitioned the hard drive and the
files that were in folders in root went bye bye.

I know I'm not _supposed_ to put stuff there, but it was a family video
project I was putting together for my wife for Christmas, and she would have
seen it anywhere else.

There should have at least been a notice or a warning or some kind of
confirmation. But there was nothing.

Nothing in the "Relocated" folder, either.

~~~
ahbyb
Don't you have to disable SIP to be able to put files there?

~~~
reaperducer
In Mojave, I didn't. I don't recall it even asking for an administrator's
password, though it was seven months ago when I created the directories.

------
Alex3917
Not surprising. The new Podcasts app deleted years of downloaded podcasts when
I updated, including a lot that are no longer hosted on the web. For some
reason the "sensible default" in the new app is to delete anything beyond the
most recent ten episodes. Now I need to remember to restore from backup before
it gets overwritten, heh.

~~~
derefr
> For some reason

Giving you the other side of this: Podcasts was essentially a disk-space-leak
made app, if you subscribed to any podcasts that you never actually listened
to (but still listened to others, and therefore regularly opened the app.) It
would just pile up new unplayed episodes forever, eventually taking up tens of
GBs of space, on a device that doesn't have all that much space to spare.

~~~
Alex3917
> It would just pile up new unplayed episodes forever

AKA exactly the desired behavior.

~~~
callalex
Humans are forgetful, sometimes it’s nice to have machines help us organize
things.

~~~
forgotmypw3
'organize' != 'delete'

------
newscracker
I’ve never used Mail because I’ve never felt comfortable with Apple’s apps
when it comes to long term data storage. Here Mail is said to delete data.
This has happened before, IIRC. Someone in this discussion has written that
their old downloaded podcast episodes were deleted on upgrade. In the distant
past, Apple has also broken compatibility in data formats (for its iWork apps)
and left those who upgraded with almost nothing.

Apple seems to focus too much on reinventing things, as if every app team gets
a new (and inexperienced) set of developers each year and they see whatever is
there as bad, incomprehensible code...so they write things from scratch,
introducing tons of bugs and removing backward compatibility. Look at its app
history and you’ll see a lot of work just thrown away every few years, only to
be replaced with crippled applications that would take long to mature but
aren’t allowed to.

Mozilla Thunderbird is “boring software”, and hasn’t made huge strides in UX
in the last several years, but I trust it more than I would ever trust Apple
Mail.

If I want “office software”, I have LibreOffice, which has its own issues in
UX, but I can trust that it won’t drop backward compatibility at the drop of a
hat.

If I want a browser, there’s Firefox. Safari 13 has become just ok now (from
decent) because of the new extensions system that has junked all old
extensions. It’s fine for firing up an ephemeral window, and it still provides
the best battery life.

I feel the days of power users on the platform are numbered. I doubt if
AppleScript and Automator will survive and be around in the next two years.

Is there any Apple app on Mac that’s been great and really improved in a
stable manner?

~~~
Santosh83
> If I want a browser, there’s Firefox. Safari 13 has become just ok now (from
> decent) because of the new extensions system that has junked all old
> extensions.

To be fair Firefox did that recently with their transition to WebExtensions
too, and Chrome will soon do something similar when they move to Manifest v3.
Sadly all mainstream browsers have become "move fast and break stuff", mainly
in their desperate bid to keep pace with the de facto standard that is Chrome.
But most of them don't have browser dev teams the size of Chrome's...

~~~
newscracker
Firefox’s transition to WebExtensions has caused pain to developers and users,
but there was a warning for some years about the transition. I still don’t
like where the WebExtensions API support is, and Mozilla hasn’t done much for
erstwhile popular extensions like Tab Mix Plus and many others. The case with
Safari 13, IIRC, is that extensions have to be developed in Swift and have
lesser access than before.

While I get the privacy benefits with block lists that have been/are
being/will be implemented in these browsers, the overall extensions scene
doesn’t look very good. Hopefully Firefox will delay or not go with everything
that Manifest V3 proposes, whenever that becomes standard in Chrome.

------
segmondy
I have earned many thumbs down on the net for saying that Apple can't write
software for shit. Apple is a design company, they make nice hardware, nice
really looking hardware and sometimes performing hardware. That's it, a nice
hardware design company. There software is straight up garbage and has been
for a long time. Just as I have always been suspicious of those whose main OS
is windows and they are not writing native windows app, I'm suspicious of
those who use Apple if there full time job is not developing iOS apps. I do
own a used Mac mini I bought a few years ago for the solo purpose of
developing iOS apps. First time I ever upgraded it after being annoyed to
death, it trashed the system and I had to do a fresh reinstall.

~~~
blub
Blaming "the company" for bugs in complex human-machine systems doesn't really
say anything insightful, actionable or useful.

Android, Linux, Windows, macOS and iOS are all broken, just in different ways.
This is the quality that can be reached for mass-market consumer products with
the standard development processes.

~~~
auggierose
Yeah, good point. I am quite happy with Catalina so far so I have battled
through a few issues. I think people basically have no idea what it takes to
deliver perfectly functioning software. Basically, you need to combine user
testing, design and theorem proving. It would be just too costly even for
Apple.

------
pcr910303
As a daily Mac user who started to use macOS (OS X) about 7-8 years ago, I
find the insurmountable number of bugs of macOS Catalina alarming. Don’t get
me wrong, the situation is still much, much compared to Windows or Linux[0],
buy it is alarming to see the general quality of macOS software to decrease.

I personally think it’s due to Apple engineers trying to do so much; I
remember being impressed by the number of new features and changes introduced
this year while watching the WWDC, but it looks like Apple couldn’t keep up
its own enthusiasm.

Project Catalyst was poorly executed; I was disappointed that Catalyst doesn’t
default to ‘HIG-respecting’ AppKit controls that correspond well with the
UIKit equivalents (so that modal form sheets in UIKit are translated into
floating windows, e.g.), and the inability to mix in AppKit controls and UIKit
ones into the same view hierarchy (NSColorWell or NSPopUpButton doesn’t have
UIKit equivalents), e.g.

SwiftUI is great in theory, but the tooling is immature, it’s not available to
write any decently complex apps with them.

The iCloud changes were reverted right before Catalina’s release; looks like
the iCloud team didn’t have enough manpower to fix all the bugs until the
release.

It’s concerning, as one of the premise of macOS was that it works as expected,
though that now the newly introduced parts doesn’t. I’m expecting a
stabilizing release for macOS 10.16 akin to the stone-stable 10.14 Mojave, but
I don’t remember 10.13 High Sierra to be unstable like this one.

[0]: For Linux users who don’t agree with this: I’ve never set up a Linux
desktop system with all the hardware working without doing any ‘geek’ stuff
like running some shell commands. And no, the fact that Apple only allows to
use macOS only on its own computers isn’t an excuse. And no, even on well
supported laptops like the ThinkPad, there are a furious amount of bugs that
need ‘configuring’

~~~
akkawwakka
The company and its engineering teams are absolutely subjected to delivering
too much.

I think the prior perceived quality of Apple software was propped up by a lot
of people internally grinding very hard on a far smaller set of products than
the company ships today. That might work when you are at 10k people, not 120k.

It’s really time for Apple to make a good faith effort to improve its software
development process. Honestly it seems more like an executive leadership
issue, incessant and hasty product changes come at the cost of stability.

------
elevenbits
It's temping to treat this as more of the same "Catalina is buggy, Apple is
doomed" news, but note that Mail.app has ALWAYS been less than rock solid. For
some reason, it seems to be a prime target for new features and
reconfiguration every release, resulting in a lot of churn which
unsurprisingly brings about bugs like this. A cursory search indicates a bug
about some messages not showing up in 10.8, a Gmail issue in 10.9, VIP issues
in 10.11, etc. But hey, we have gratuitous, cannot-be-disabled window
animations when replying to a message, so what's a little data loss compared
to that?

------
saagarjha
Is there a way to detect if you have data loss? It sure _looks_ like Mail has
my emails, but I'm not sure…

~~~
dv_dt
Perhaps if the mail database were blockchained or at least merkle tree linked
or otherwise metadata secured.

~~~
eli
Or just backed up.

~~~
nitrogen
A hash tree for email actually seems like a semi-decent idea for verifying
integrity of a synced mailbox.

~~~
journalctl
So use a hash function like in the olden days.

~~~
nitrogen
The benefit of either a tree or a sequence or hashes is that you could
identify where and when the active mailbox differs from the backups. If each
message is its own separate file then it's less interesting.

------
jquery
My iCloud backup, with years of data, including apps which only had local
storage, was completely borked when I upgraded to iOS 13 (on my iPhone XS). My
phone would enter a boot loop during the iCloud restore process, and I tried
15 different restores (different iOS 13 versions including beta versions,
iTunes backups, a couple different types of restores they have at the Genius
Bar, a direct phone-to-phone restore, curating my iCloud backup with only the
most important apps, etc). None of them worked, all ended in a boot loop.
Apple Support basically gave up on me, telling me my "backup was corrupted".

In the end I had to start with a fresh iOS install, which was very
disappointing, as my years of accumulated app data were lost. I manually
backed up what I could, but some apps had their data lost forever, and I
wasted many hours of time.

Very disappointing.

~~~
forgotmypw3

        I feel your pain. I hope you remember in the future:
    
        Unless a backup can be verified, it is not a backup.
    
        Backing up to a complex or binary format is trouble.

~~~
jquery
So true, but I’m not sure what I could have done here, except stay on iOS 12*
indefinitely. This wasn’t a case of having an invalid backup per se (I was
able to restore my phone back to iOS 12), this was a case of being unable to
port forward data from iOS 12 to iOS 13. In other words, a perfectly working
system could not be upgraded via Apple’s upgrade process, nor did Apple
provide good workarounds for this scenario, such as allowing the restoration
of individual apps.

That’s why I’m extra disappointed in Apple. I did everything by the book,
including testing my backups, and my data was still lost.

~~~
forgotmypw3
I think what you can do now is avoid complex, binary, and/or proprietary
formats for your data, because they are more difficult to back up and restore.

You can also learn to not trust software which promiess you the world, but
doesn't let you see its internals.

~~~
jquery
Yeah, lesson learned. Fortunately my most critical data was backed up
elsewhere. This seems like an inherent issue with iOS, I will consider
migrating to a different platform. Any suggestions other than Android?

~~~
forgotmypw3
See which iOS apps can export/import plaintext or other common formats,
especially in an automated way.

------
atmosx
It’s a good idea to create a bootable backup and come up with a clean install
of macOS with each major release. Every time I updated the existing system
straight up, I had minor or major issues solved by a clean install.

------
plg
good LORD

if this is true how are we supposed to trust apple with our information?

BTW since updating my iPhone & iPad to iOS 13, and my desktop to MacOS 10.15,
the Notes app does not propagate changes unless I force-quit the app and then
restart it.

Entering a new note, and quitting the app, the new note does not propagate to
my other devices. If I re-open the Notes app then the update happens. WTF

A walled garden ecosystem’s main raison d’etre is for everything to work
together. If it doesn’t, it defeats the purpose.

I’ve been an Apple advocate for a long time but things are getting dicey.
Perhaps my macs will turn into defacto expensive chromebooks. In other words
use them to run chrome and in turn gsuite everything, and nothing else.

God awful

~~~
brianprovost
I've also had issues with the iOS 13 on an iPhone X. Mail notifications appear
but the messages don't download for 30+ seconds, and sometimes notifications
don't disappear.

Other people are also having issues with mail on iOS:
[https://twitter.com/CliffordAsness/status/118240716828649472...](https://twitter.com/CliffordAsness/status/1182407168286494726)

~~~
tyre
Just got an 11 Pro and some notifications don’t vibrate, other notifications
no longer show up even though they have permissions to and are set to.
Sometimes iMessages won’t vibrate either.

It’s a mess and I can’t trust my phone to notify me. Now I have to constantly
be checking it

~~~
erichurkman
Add in that alarms randomly don't fire, or fire at the wrong volume. I'm using
my old phone as my clock and timer. I wonder if it's related to the bonkers
notification settings.

Either way, disaster of a phone, and disaster of an OS.

------
userbinator
I don't know if Apple has changed the format again, but in the past at least
it seemed reasonably sane and filesystem-based:

[http://mike.laiosa.org/2009/03/01/emlx.html](http://mike.laiosa.org/2009/03/01/emlx.html)

[https://wiki.fileformat.com/email/emlx/](https://wiki.fileformat.com/email/emlx/)

It doesn't seem that hard to write some more tools to manipulate them.

~~~
rcarmo
I have had code to handle emlx for over 10 years:

[https://taoofmac.com/space/blog/2008/03/03/2211](https://taoofmac.com/space/blog/2008/03/03/2211)

The thing here is that

a) there are also a number of SQLite databases that are used by Mail to store
metadata and sundry

b) Mail's IMAP handling has been notoriously buggy at times

My guess is that this particular data loss bug in Catalina stems from a
combination of the IMAP implementation and the metadata storage, but since
they keep playing whack-a-mole inside ~/Library/Mail, I can't offer more
details.

------
jbverschoor
> Moving messages between mailboxes, both via drag-and-drop and AppleScript,
> can result in a blank message (only headers) on the Mac. If the message was
> moved to a server mailbox, other devices see the message as deleted. And
> eventually this syncs back to the first Mac, where the message disappears as
> well.

Actually this was already a problem on Mohave. I lost all my mail from one
mailbox when moving messages from one folder to another (gmail)

------
ggregoire
Why do people use Mail? (genuine question)

~~~
geerlingguy
It's very fast (native app), it supports practically every type of mail
account ever, everything can be stored locally (great for offline batch
processing of emails), and there are keyboard shortcuts for everything. It
takes a bit of customization to get a layout that works nicely for my workflow
(I use the classic layout).

There are a bunch of other 'efficient' mail apps, but if you just need basic
features and don't go for some exotic or trendy workflow, Mail works fine.

I don't upgrade to the latest OS for at least a few weeks, though, because if
something like this is systemic, it will be fixed in the .1 or .2 release.

Also, always keep at least one local backup (I have Time Machine for that),
and at least one remote backup.

~~~
kitsunesoba
It’s also so much better for working with massive amounts of mail compared to
Gmail and other webmails. In Mail I can work through many tens or hundreds of
messages quickly and easily. With Gmail I often feel like I’m jumping through
hoops to do the same thing.

~~~
tandav
A use Mail.app but to be fair. Search in mail.google.com is much faster than
in Mail.app (when you have thousands of mails)

------
techslave
you people are going batshit crazy over completely unsubstantiated report.

It even says,

> I don’t know whether these are due to Mail bugs or to other factors such as
> problems on the Mac or with the mail server.

