Hi,

if I understand https://bugzilla.mozilla.org/show_bug.cgi?id=1294027
correctly, setting mail.smtp.useSenderForSmtpMailFrom to true (which is
the default) should make it possible to override the address used in the
SMTP "MAIL FROM" command by specifying a custom From header.

To be able to specify a custom From header, I set
mail.compose.other.header = "From" and selected that from the drop-down
list in the compose window. However, "MAIL FROM" still contained the
address of the selected identity. I debugged the SMTP dialogue by
setting MOZ_LOG and MOZ_LOG_FILE.

Since this feature was introduced with Thunderbird 59 I thought it might
be supported by SeaMonkey. Or maybe I'm using it wrongly.

On Sun, 17 Dec 2023 11:24:51 +0100, mike wrote:

> Hi,
>
> if I understand https://bugzilla.mozilla.org/show_bug.cgi?id=1294027
> correctly, setting mail.smtp.useSenderForSmtpMailFrom to true (which is
> the default) should make it possible to override the address used in the
> SMTP "MAIL FROM" command by specifying a custom From header.
>
> To be able to specify a custom From header, I set
> mail.compose.other.header = "From" and selected that from the drop-down
> list in the compose window. However, "MAIL FROM" still contained the
> address of the selected identity. I debugged the SMTP dialogue by
> setting MOZ_LOG and MOZ_LOG_FILE.
>
> Since this feature was introduced with Thunderbird 59 I thought it might
> be supported by SeaMonkey. Or maybe I'm using it wrongly.

MAIL FROM will use the per-message From header. That per-message From
header is set by editing the From field at the _top_ of the compose
window, as shown in this screen-shot.

  Screen-shot: <http://img4.imagetitan.com/img.php?image=27_ulmi9j__edit-the-from-field-at-the-top-of-the-seamonkey-compose-window.gif>

--
Kind regards
Ralph Fox
🦊

Every shoe fits not every foot.

On 22.12.2023 08:32, Ralph Fox wrote:
> On Sun, 17 Dec 2023 11:24:51 +0100, mike wrote:
>
>> Hi,
>>
>> if I understand https://bugzilla.mozilla.org/show_bug.cgi?id=1294027
>> correctly, setting mail.smtp.useSenderForSmtpMailFrom to true (which is
>> the default) should make it possible to override the address used in the
>> SMTP "MAIL FROM" command by specifying a custom From header.
>>
>> To be able to specify a custom From header, I set
>> mail.compose.other.header = "From" and selected that from the drop-down
>> list in the compose window. However, "MAIL FROM" still contained the
>> address of the selected identity. I debugged the SMTP dialogue by
>> setting MOZ_LOG and MOZ_LOG_FILE.
>>
>> Since this feature was introduced with Thunderbird 59 I thought it might
>> be supported by SeaMonkey. Or maybe I'm using it wrongly.
>
>
> MAIL FROM will use the per-message From header. That per-message From
> header is set by editing the From field at the _top_ of the compose
> window, as shown in this screen-shot.
>
>   Screen-shot: <http://img4.imagetitan.com/img.php?image=27_ulmi9j__edit-the-from-field-at-the-top-of-the-seamonkey-compose-window.gif>
>

Yes, I know that. According to the linked bug report it should be
possible to have a MAIL FROM that's *different* from the identity's address.

Use case is that recently my mail provider started enforcing that the
domain of the SMTP login must match the domain of the MAIL FROM address.
Since MAIL FROM is the same as the "From:" address of the identity I can
no longer send mails with an address from a different domain (in this
case an address I registered at a pure forwarding service).

So what I would need, and what worked until recently, is (pseudo SMTP
dialogue):

LOGIN my_login@my_domain.com
MAIL FROM: my_identity@my_domain.com
DATA
From: <other_identity@other_domain.com>
..

On Fri, 22 Dec 2023 09:43:05 +0100, mike wrote:
> On 22.12.2023 08:32, Ralph Fox wrote:
>> On Sun, 17 Dec 2023 11:24:51 +0100, mike wrote:
>>
>>> Hi,
>>>
>>> if I understand https://bugzilla.mozilla.org/show_bug.cgi?id=1294027
>>> correctly, setting mail.smtp.useSenderForSmtpMailFrom to true (which is
>>> the default) should make it possible to override the address used in the
>>> SMTP "MAIL FROM" command by specifying a custom From header.
>>>
>>> To be able to specify a custom From header, I set
>>> mail.compose.other.header = "From" and selected that from the drop-down
>>> list in the compose window. However, "MAIL FROM" still contained the
>>> address of the selected identity. I debugged the SMTP dialogue by
>>> setting MOZ_LOG and MOZ_LOG_FILE.
>>>
>>> Since this feature was introduced with Thunderbird 59 I thought it might
>>> be supported by SeaMonkey. Or maybe I'm using it wrongly.
>>
>>
>> MAIL FROM will use the per-message From header. That per-message From
>> header is set by editing the From field at the _top_ of the compose
>> window, as shown in this screen-shot.
>>
>>   Screen-shot: <http://img4.imagetitan.com/img.php?image=27_ulmi9j__edit-the-from-field-at-the-top-of-the-seamonkey-compose-window.gif>
>>
>
> Yes, I know that. According to the linked bug report it should be
> possible to have a MAIL FROM that's *different* from the identity's address.
>
> Use case is that recently my mail provider started enforcing that the
> domain of the SMTP login must match the domain of the MAIL FROM address.
> Since MAIL FROM is the same as the "From:" address of the identity I can
> no longer send mails with an address from a different domain (in this
> case an address I registered at a pure forwarding service).
>
> So what I would need, and what worked until recently, is (pseudo SMTP
> dialogue):
>
> LOGIN my_login@my_domain.com
> MAIL FROM: my_identity@my_domain.com
> DATA
> From: <other_identity@other_domain.com>
> .

If you want the MAIL FROM address to be different to the "From:"
address, then do these:

1. Set mail.smtp.useSenderForSmtpMailFrom to false (not true).

When mail.smtp.useSenderForSmtpMailFrom is true, the SMTP FROM
is overridden with whatever is in the "From:" address. This
means they will be the *same* -- not what you are asking for.

2. Forget the mail.compose.other.header = "From". This will not
help. Best reset this preference so you will not accidentally
try to use it again.

3. Set the email account's default identity to have the same email
address that you want in the MAIL FROM.

4. Start a new email. The From field at the _top_ of the compose
window will show the default identity with the address you want
to have in the MAIL FROM (provided you have done #3 above).

Now *edit* the From field at the _top_ of the compose window to
have the name and address you want to appear in the "From:" field.
IMPORTANT:
* Change the From field by putting the cursor in the field and
overtyping.
* Do *not* change the From field by picking another identity from
the drop-down. Picking another identity this way will also
change the MAIL FROM.

Before bug #1294027 was implemented, it was possible to have a
MAIL FROM that is *different* from the sender address you provide
with an email. Bug #1294027 was to make them the same. To revert
to the previous behaviour (which can allow them to be different),
set mail.smtp.useSenderForSmtpMailFrom to false.

--
Kind regards
Ralph Fox
🦊

Better half a loaf then no bread.

Ralph Fox wrote:
> On Fri, 22 Dec 2023 09:43:05 +0100, mike wrote:
>> On 22.12.2023 08:32, Ralph Fox wrote:
>>> On Sun, 17 Dec 2023 11:24:51 +0100, mike wrote:
>>>
>>>> Hi,
>>>>
>>>> if I understand https://bugzilla.mozilla.org/show_bug.cgi?id=1294027
>>>> correctly, setting mail.smtp.useSenderForSmtpMailFrom to true (which is
>>>> the default) should make it possible to override the address used in the
>>>> SMTP "MAIL FROM" command by specifying a custom From header.
>>>>
>>>> To be able to specify a custom From header, I set
>>>> mail.compose.other.header = "From" and selected that from the drop-down
>>>> list in the compose window. However, "MAIL FROM" still contained the
>>>> address of the selected identity. I debugged the SMTP dialogue by
>>>> setting MOZ_LOG and MOZ_LOG_FILE.
>>>>
>>>> Since this feature was introduced with Thunderbird 59 I thought it might
>>>> be supported by SeaMonkey. Or maybe I'm using it wrongly.
>>>
>>>
>>> MAIL FROM will use the per-message From header. That per-message From
>>> header is set by editing the From field at the _top_ of the compose
>>> window, as shown in this screen-shot.
>>>
>>>   Screen-shot: <http://img4.imagetitan.com/img.php?image=27_ulmi9j__edit-the-from-field-at-the-top-of-the-seamonkey-compose-window.gif>
>>>
>>
>> Yes, I know that. According to the linked bug report it should be
>> possible to have a MAIL FROM that's *different* from the identity's address.
>>
>> Use case is that recently my mail provider started enforcing that the
>> domain of the SMTP login must match the domain of the MAIL FROM address.
>> Since MAIL FROM is the same as the "From:" address of the identity I can
>> no longer send mails with an address from a different domain (in this
>> case an address I registered at a pure forwarding service).
>>
>> So what I would need, and what worked until recently, is (pseudo SMTP
>> dialogue):
>>
>> LOGIN my_login@my_domain.com
>> MAIL FROM: my_identity@my_domain.com
>> DATA
>> From: <other_identity@other_domain.com>
>> .
>
> If you want the MAIL FROM address to be different to the "From:"
> address, then do these:
>
> 1. Set mail.smtp.useSenderForSmtpMailFrom to false (not true).
>
> When mail.smtp.useSenderForSmtpMailFrom is true, the SMTP FROM
> is overridden with whatever is in the "From:" address. This
> means they will be the *same* -- not what you are asking for.
>
> 2. Forget the mail.compose.other.header = "From". This will not
> help. Best reset this preference so you will not accidentally
> try to use it again.
>
> 3. Set the email account's default identity to have the same email
> address that you want in the MAIL FROM.
>
> 4. Start a new email. The From field at the _top_ of the compose
> window will show the default identity with the address you want
> to have in the MAIL FROM (provided you have done #3 above).
>
> Now *edit* the From field at the _top_ of the compose window to
> have the name and address you want to appear in the "From:" field.
> IMPORTANT:
> * Change the From field by putting the cursor in the field and
> overtyping.
> * Do *not* change the From field by picking another identity from
> the drop-down. Picking another identity this way will also
> change the MAIL FROM.
>
>
> Before bug #1294027 was implemented, it was possible to have a
> MAIL FROM that is *different* from the sender address you provide
> with an email. Bug #1294027 was to make them the same. To revert
> to the previous behaviour (which can allow them to be different),
> set mail.smtp.useSenderForSmtpMailFrom to false.
>
>
>

I have an account with several aliases, my understanding is that I can
use this feature to apparently send an email from the "alias address",
something I've been wanting to be able to do for years.
This way they don't get to see my underlying "real address", but I do
get to see any replies normally.
What's the point of that? I use aliases because I have had to abandon
addresses in the past due to excess spam. There's a lot less to lose if
I just have to junk an alias.

On 23.12.2023 22:20, Don Vito Martinelli wrote:
> Ralph Fox wrote:
>> On Fri, 22 Dec 2023 09:43:05 +0100, mike wrote:
>>> On 22.12.2023 08:32, Ralph Fox wrote:
>>>> On Sun, 17 Dec 2023 11:24:51 +0100, mike wrote:
>>>>
>>>>> Hi,
>>>>>
>>>>> if I understand https://bugzilla.mozilla.org/show_bug.cgi?id=1294027
>>>>> correctly, setting mail.smtp.useSenderForSmtpMailFrom to true
>>>>> (which is
>>>>> the default) should make it possible to override the address used
>>>>> in the
>>>>> SMTP "MAIL FROM" command by specifying a custom From header.
>>>>>
>>>>> To be able to specify a custom From header, I set
>>>>> mail.compose.other.header = "From" and selected that from the
>>>>> drop-down
>>>>> list in the compose window. However, "MAIL FROM" still contained the
>>>>> address of the selected identity. I debugged the SMTP dialogue by
>>>>> setting MOZ_LOG and MOZ_LOG_FILE.
>>>>>
>>>>> Since this feature was introduced with Thunderbird 59 I thought it
>>>>> might
>>>>> be supported by SeaMonkey. Or maybe I'm using it wrongly.
>>>>
>>>>
>>>> MAIL FROM will use the per-message From header.  That per-message From
>>>> header is set by editing the From field at the _top_ of the compose
>>>> window, as shown in this screen-shot.
>>>>
>>>>    Screen-shot: <http://img4.imagetitan.com/img.php?image=27_ulmi9j__edit-the-from-field-at-the-top-of-the-seamonkey-compose-window.gif>
>>>>
>>>>
>>>
>>> Yes, I know that. According to the linked bug report it should be
>>> possible to have a MAIL FROM that's *different* from the identity's
>>> address.
>>>
>>> Use case is that recently my mail provider started enforcing that the
>>> domain of the SMTP login must match the domain of the MAIL FROM address.
>>> Since MAIL FROM is the same as the "From:" address of the identity I can
>>> no longer send mails with an address from a different domain (in this
>>> case an address I registered at a pure forwarding service).
>>>
>>> So what I would need, and what worked until recently, is (pseudo SMTP
>>> dialogue):
>>>
>>> LOGIN my_login@my_domain.com
>>> MAIL FROM: my_identity@my_domain.com
>>> DATA
>>> From: <other_identity@other_domain.com>
>>> .
>>
>> If you want the MAIL FROM address to be different to the "From:"
>> address, then do these:
>>
>>   1.  Set mail.smtp.useSenderForSmtpMailFrom to false (not true).
>>
>>       When mail.smtp.useSenderForSmtpMailFrom is true, the SMTP FROM
>>       is overridden with whatever is in the "From:" address.  This
>>       means they will be the *same* -- not what you are asking for.
>>
>>   2.  Forget the mail.compose.other.header = "From".  This will not
>>       help.  Best reset this preference so you will not accidentally
>>       try to use it again.
>>
>>   3.  Set the email account's default identity to have the same email
>>       address that you want in the MAIL FROM.
>>
>>   4.  Start a new email.  The From field at the _top_ of the compose
>>       window will show the default identity with the address you want
>>       to have in the MAIL FROM (provided you have done #3 above).
>>
>>       Now *edit* the From field at the _top_ of the compose window to
>>       have the name and address you want to appear in the "From:" field.
>>       IMPORTANT:
>>       *  Change the From field by putting the cursor in the field and
>>          overtyping.
>>       *  Do *not* change the From field by picking another identity from
>>          the drop-down.  Picking another identity this way will also
>>          change the MAIL FROM.
>>
>>
>> Before bug #1294027 was implemented, it was possible to have a
>> MAIL FROM that is *different* from the sender address you provide
>> with an email.  Bug #1294027 was to make them the same.  To revert
>> to the previous behaviour (which can allow them to be different),
>> set mail.smtp.useSenderForSmtpMailFrom to false.
>>
>>
>>
>
> I have an account with several aliases, my understanding is that I can
> use this feature to apparently send an email from the "alias address",
> something I've been wanting to be able to do for years.

Yes, that's exactly my use case and it works as described by Ralph but
you don't have to select the account's default identity.

So this is what I did:

* Set mail.smtp.useSenderForSmtpMailFrom to false
* Start a new mail
* Select identity my_identity@my_domain.com (which is configured to use
my_login@my_domain.com for SMTP login)
* Edit the From: field to the alias other_identity@other_domain.com
* Send mail

Now the SMTP log shows:
SMTP AuthLoginStep1() for my_login@my_domain.com
MAIL FROM: my_identity@my_domain.com

And the mail has the From: header of the alias
other_identity@other_domain.com (with the drawback that Return-Path is
my_identity@my_domain.com so it's not really hidden).

I just didn't know that you could edit the From: field where you select
the identity and apparently I misunderstood
mail.smtp.useSenderForSmtpMailFrom (which needs to be false not true).

Thanks for clarifying that!

Ralph Fox wrote:
> On Sun, 17 Dec 2023 11:24:51 +0100, mike wrote:
>
>> Hi,
>>
>> if I understand https://bugzilla.mozilla.org/show_bug.cgi?id=1294027
>> correctly, setting mail.smtp.useSenderForSmtpMailFrom to true (which is
>> the default) should make it possible to override the address used in the
>> SMTP "MAIL FROM" command by specifying a custom From header.
>>
>> To be able to specify a custom From header, I set
>> mail.compose.other.header = "From" and selected that from the drop-down
>> list in the compose window. However, "MAIL FROM" still contained the
>> address of the selected identity. I debugged the SMTP dialogue by
>> setting MOZ_LOG and MOZ_LOG_FILE.
>>
>> Since this feature was introduced with Thunderbird 59 I thought it might
>> be supported by SeaMonkey. Or maybe I'm using it wrongly.
>
>
> MAIL FROM will use the per-message From header. That per-message From
> header is set by editing the From field at the _top_ of the compose
> window, as shown in this screen-shot.
>
>   Screen-shot: <http://img4.imagetitan.com/img.php?image=27_ulmi9j__edit-the-from-field-at-the-top-of-the-seamonkey-compose-window.gif>
>
>

Thanks, I finally had cause to use this and it worked perfectly.