2011341 - Slowness in Send

Status: RESOLVED DUPLICATE of bug 1993576

(Thunderbird :: Untriaged, defect)

Description

[Paul Szabo]

Steps to reproduce:

I now use Thunderbird 147.0 on Linux, on either Debian trixie or
Ubuntu noble, and since a few versions ago I observe occasional
slowness in Send. Most often I observe such slowness when sending
from my Office365 account, but on fewer occasions have observed
similar slowness on sending both from both my gmail account and
from my "local" SMTP account.

After setting mailnews.smtp.loglevel=Debug, logs show a delay
between the second EHLO and server Hello:

08:11:38.548 mailnews.smtp: Connecting to smtp://smtp.office365.com:587 SmtpClient.sys.mjs:152:19
08:11:38.678 mailnews.smtp: Connected SmtpClient.sys.mjs:440:17
08:11:38.680 mailnews.smtp: S: 220 SY5P282CA0133.outlook.office365.com Microsoft ESMTP MAIL Service ready at Sat, 17 Jan 2026 21:11:38 +0000 [08DE55C11ADBDC7B] SmtpClient.sys.mjs:463:17
08:11:38.681 mailnews.smtp: C: EHLO [192.168.0.187] SmtpClient.sys.mjs:679:19
08:11:38.691 mailnews.smtp: S: 250-SY5P282CA0133.outlook.office365.com Hello [49.176.127.122] SmtpClient.sys.mjs:463:17
08:11:38.691 mailnews.smtp: C: STARTTLS SmtpClient.sys.mjs:679:19
08:11:38.700 mailnews.smtp: S: 220 2.0.0 SMTP server ready SmtpClient.sys.mjs:463:17
08:11:38.701 mailnews.smtp: C: EHLO [192.168.0.187] SmtpClient.sys.mjs:679:19
08:12:15.912 mailnews.smtp: S: 250-SY5P282CA0133.outlook.office365.com Hello [49.176.127.122] SmtpClient.sys.mjs:463:17
08:12:15.940 mailnews.smtp: Possible auth methods: XOAUTH2 SmtpClient.sys.mjs:965:17
08:12:15.941 mailnews.smtp: Current auth method: XOAUTH2 SmtpClient.sys.mjs:719:17
08:12:15.941 mailnews.smtp: Authentication via AUTH XOAUTH2 SmtpClient.sys.mjs:748:21
08:12:15.961 mailnews.smtp: C: Logging suppressed (it probably contained auth information) SmtpClient.sys.mjs:675:19
08:12:16.175 mailnews.smtp: S: 235 2.7.0 Authentication successful SmtpClient.sys.mjs:463:17
08:12:16.175 mailnews.smtp: Authentication successful. SmtpClient.sys.mjs:1195:17
08:12:16.177 mailnews.smtp: C: MAIL FROM:<[e-mail]> BODY=8BITMIME SIZE=2236 SmtpClient.sys.mjs:679:19
08:12:16.213 mailnews.smtp: S: 250 2.1.0 Sender OK SmtpClient.sys.mjs:463:17
08:12:16.213 mailnews.smtp: MAIL FROM successful, proceeding with 1 recipients SmtpClient.sys.mjs:1230:17
08:12:16.213 mailnews.smtp: Adding recipient... SmtpClient.sys.mjs:1235:17
08:12:16.213 mailnews.smtp: C: RCPT TO:<[e-mail]> SmtpClient.sys.mjs:679:19
08:12:16.234 mailnews.smtp: S: 250 2.1.5 Recipient OK SmtpClient.sys.mjs:463:17
08:12:16.234 mailnews.smtp: Total RCPTs during this connection: 1 SmtpClient.sys.mjs:1297:19
08:12:16.234 mailnews.smtp: RCPT TO done. Proceeding with payload. SmtpClient.sys.mjs:1300:19
08:12:16.234 mailnews.smtp: C: DATA SmtpClient.sys.mjs:679:19
08:12:16.255 mailnews.smtp: S: 354 Start mail input; end with <CRLF>.<CRLF> SmtpClient.sys.mjs:463:17
08:12:16.255 mailnews.smtp: Sending 2236 bytes of payload SmtpClient.sys.mjs:646:17
08:12:16.926 mailnews.smtp: S: 250 2.0.0 OK <[e-mail]> [Hostname=MEYPR01MB7280.ausprd01.prod.outlook.com] SmtpClient.sys.mjs:463:17
08:12:16.926 mailnews.smtp: Message sent successfully. SmtpClient.sys.mjs:1359:21
08:12:21.945 mailnews.smtp: C: QUIT SmtpClient.sys.mjs:679:19
08:12:21.970 mailnews.smtp: S: 221 2.0.0 Service closing transmission channel SmtpClient.sys.mjs:463:17
08:12:22.094 mailnews.smtp: Socket closed. SmtpClient.sys.mjs:563:17

As something of a workaround, it seems that while the Send window
is delayed, it is possible to click on a different mail folder in
the left menu of the main Thunderbird window, to cause the message
to be sent immediately. This seems to work best when clicking on a
mail folder in an account different from the one used to send.

How would I debug this issue, and/or demonstrate the interaction
between the send and the click on another folder?

Thanks, Paul

Paul Szabo [e-mail] www.maths.usyd.edu.au/u/psz
School of Mathematics and Statistics University of Sydney Australia