Help with NOT deleting mail

[gilby101]

Gmail says I'm using 9.28GB. Even if you assume the 3.62GB figure, that's still a lot less.

I agree that is a big difference. Nothing like what I get.

 

[FreakinEurekan]

I agree that is a big difference. Nothing like what I get.

Here's a hypothesis:

When you add a Mail account to a Mac, attachments aren't downloaded unless the specific Mail message is opened on that Mac. Like I mentioned this Mac is under 2 years old, but I have Mail going back to 2013.

Would that line up with your typical usage? i.e., are the majority of the messages currently in your gmail, messages you've read on your current Mac?

 

[gilby101]

Would that line up with your typical usage? i.e., are the majority of the messages currently in your gmail, messages you've read on your current Mac?

I have read (or glanced at) all the messages on my Mac. And I do archive old messages with Eagle Filer to keep my Apple Mail under control. My iMac was last rebuilt in 2019 and there is nothing older than 2 years in my Apple Mai.

Also, for all email services I do have "Download Attachments" - "All". The default? I have changed that to "None" to see how that changes behaviour. I am assuming that this is a switch for "MIME Parts On Demand".

It doesn't help that there is no (I can't find any) specification for how Apple Mail behaves at the IMAP communication level.

Seems like I am coming round to your thinking about Apple Mail!!

 

[FreakinEurekan]

Also, for all email services I do have "Download Attachments" - "All". The default? I have changed that to "None" to see how that changes behaviour. I am assuming that this is a switch for "MIME Parts On Demand".

I was completely unaware of that setting - mine is set to "Recent," so I presume that's the default setting? If I changed it, I've completely forgotten - two of the Macs were set up "From scratch" within the last year or two and I'm confident I didn't change that setting on them. But in both cases I signed into my iCloud and that probably brought my Mail account over, so perhaps it's synced by iCloud Keychain? Not totally sure.

Reading the documentation on that setting, it apparently doesn't apply to "Media" attachments like photos and PDFs - just to "other types of attachments (such as spreadsheets or zipped files)." However when I pulled up that old email from 2016/2017 it showed "Downloading" on the group of photos in that message, so it seems like older messages do suppress media download unless the email is specifically viewed on the computer.

I don't know "Exactly" how email is being optimized - but it's obvious that it is, from the behaviors I'm seeing. No idea what timeframe, etc gets optimized - if already-downloaded media or attachments get removed from local storage if not viewed in some period of time - etc. But I can say - however it's working, I have no complaints.

 

[gilby101]

I was completely unaware of that setting

So was I until your comments got me to question my understanding of Apple Mail and IMAP/MIME! The default for Download Attachments may have changed for new installs.

I am not convinced of the accuracy of the Apple documentation on this setting. At least in part it may be confusing attachments that are MIME parts in the email (which are stored in the ~/Library/Mail... hierarchy) with attachments that are downloaded from URL links in the message (which I think are stored elsewhere).

I will continue to explore how to works (for my own interest).

But I can say - however it's working, I have no complaints.

My position too.

Edit:
FWIW I did some testing of what and when attachments get downloaded when using "Download Attachments" - "None".
1. No MIME attachments are downloaded when mail is delivered to the Inbox (or elsewhere).
2. Image attachments are downloaded when a message is viewed. Based on the help, this applies to all media types.
3. Others (a spreadsheet in my test) are only downloaded after clicking on the attachment object in the email.
These are in line with the Apple help on this setting - expands a bit on when the two types of attachments are downloaded.

Personally, I would prefer all attachment types to only download when explicitly requested by selecting them. I don't want images to download just because I view a message. This would solve a related problem for me - in my Microsoft mail box I get lots of spam with porno images.

The last line of the help is wrong. There is not a special folder for all attachments - rather they are loaded into folders near to the message in the Mail folder tree. I think this is a change in a recent macOS upgrade.

 

[FreakinEurekan]

FWIW I did some testing of what and when attachments get downloaded when using "Download Attachments" - "None".
1. No MIME attachments are downloaded when mail is delivered to the Inbox (or elsewhere).
2. Image attachments are downloaded when a message is viewed. Based on the help, this applies to all media types.
3. Others (a spreadsheet in my test) are only downloaded after clicking on the attachment object in the email.
These are in line with the Apple help on this setting - expands a bit on when the two types of attachments are downloaded.

Yes, that aligns with my testing on older messages not previously read from this computer.

The bit I'm still unsure on (and it probably doesn't really matter, in the long run) is if Mail does any sort of "trash collection" where after not viewing a message for X amount of time, the downloaded attachments are removed.

I could set up a clean Mail account and see how big THAT is - but of course, NO mail would have been opened (even stuff I just read yesterday, or last week) so of course it WOULD be smaller.

I could set up a Mail account, open a bunch of mail with attachments, and let it sit (app opened, but not receiving or opening any new mail) for 60, 90, 180 days and see if it gets any smaller. But I'm just not that curious