• Error notification

    From Jeff Layman@Jeff@invalid.invalid to alt.os.linux.mint on Fri Feb 13 08:13:47 2026
    From Newsgroup: alt.os.linux.mint

    21.3 TB 140.7.1 esr

    Not sure if this is a Mint or Thunderbird question.

    A couple of times after starting TB it threw up a message that it hadn't
    been able to connect to a mail or news server. Fine. But on the
    Thunderbird tab in the taskbar (panel) there is a red circle with a 1 in
    it. I assume that is referring to a message of some sort. But where is
    it and how do I read it? The 1 in the red circle remained after I'd read
    and closed the message that TB showed at the start.

    Mint's logs show only one reference to TB and that is when it was started.
    --
    Jeff

    --- Synchronet 3.21b-Linux NewsLink 1.2
  • From Alan K@AlanK@invalid.com to alt.os.linux.mint on Fri Feb 13 09:32:22 2026
    From Newsgroup: alt.os.linux.mint

    On 2/13/2026 3:13 AM, Jeff Layman wrote:
    21.3 TB 140.7.1 esr

    Not sure if this is a Mint or Thunderbird question.

    A couple of times after starting TB it threw up a message that it hadn't been able to connect to a mail or news server. Fine. But on the Thunderbird tab in the taskbar
    (panel) there is a red circle with a 1 in it. I assume that is referring to a message of some sort. But where is it and how do I read it? The 1 in the red circle remained
    after I'd read and closed the message that TB showed at the start.

    Mint's logs show only one reference to TB and that is when it was started.

    I see that too, I just thought it was the number of unread emails?
    --- Synchronet 3.21b-Linux NewsLink 1.2
  • From Jeff Layman@Jeff@invalid.invalid to alt.os.linux.mint on Fri Feb 13 22:07:48 2026
    From Newsgroup: alt.os.linux.mint

    On 13/02/2026 14:32, Alan K wrote:
    On 2/13/2026 3:13 AM, Jeff Layman wrote:
    21.3 TB 140.7.1 esr

    Not sure if this is a Mint or Thunderbird question.

    A couple of times after starting TB it threw up a message that it hadn't been able to connect to a mail or news server. Fine. But on the Thunderbird tab in the taskbar
    (panel) there is a red circle with a 1 in it. I assume that is referring to a message of some sort. But where is it and how do I read it? The 1 in the red circle remained
    after I'd read and closed the message that TB showed at the start.

    Mint's logs show only one reference to TB and that is when it was started. >>
    I see that too, I just thought it was the number of unread emails?

    I don't believe that it is unread mails, but as yet I don't know what.
    I'll try to get a screen shot of the tab and ask in the Mint forum.
    --
    Jeff
    --- Synchronet 3.21b-Linux NewsLink 1.2
  • From Alan K.@alan@invalid.com to alt.os.linux.mint on Fri Feb 13 18:12:05 2026
    From Newsgroup: alt.os.linux.mint

    On 2/13/26 5:07 PM, Jeff Layman wrote:
    On 13/02/2026 14:32, Alan K wrote:
    On 2/13/2026 3:13 AM, Jeff Layman wrote:
    21.3 TB 140.7.1 esr

    Not sure if this is a Mint or Thunderbird question.

    A couple of times after starting TB it threw up a message that it hadn't been able to connect to a mail or news server. Fine. But on the Thunderbird tab in the taskbar
    (panel) there is a red circle with a 1 in it. I assume that is referring to a message of some sort. But where is it and how do I read it? The 1 in the red circle remained
    after I'd read and closed the message that TB showed at the start.

    Mint's logs show only one reference to TB and that is when it was started. >>>
    I see that too, I just thought it was the number of unread emails?

    I don't believe that it is unread mails, but as yet I don't know what.
    I'll try to get a screen shot of the tab and ask in the Mint forum.

    I dual boot so I was in Windows for about 3 hours and when I returned, mine had a 3 on it.
    Sure enough I had 3 emails.
    --
    Linux Mint 22.3, Mozilla Thunderbird 140.7.1esr, Mozilla Firefox 147.0.3
    Alan K.
    --- Synchronet 3.21b-Linux NewsLink 1.2
  • From Alan K.@alan@invalid.com to alt.os.linux.mint on Fri Feb 13 18:13:31 2026
    From Newsgroup: alt.os.linux.mint

    On 2/13/26 6:12 PM, Alan K. wrote:
    On 2/13/26 5:07 PM, Jeff Layman wrote:
    On 13/02/2026 14:32, Alan K wrote:
    On 2/13/2026 3:13 AM, Jeff Layman wrote:
    21.3 TB 140.7.1 esr

    Not sure if this is a Mint or Thunderbird question.

    A couple of times after starting TB it threw up a message that it hadn't been able to connect to a mail or news server. Fine. But on the Thunderbird tab in the taskbar
    (panel) there is a red circle with a 1 in it. I assume that is referring to a message of some sort. But where is it and how do I read it? The 1 in the red circle remained
    after I'd read and closed the message that TB showed at the start.

    Mint's logs show only one reference to TB and that is when it was started. >>>>
    I see that too, I just thought it was the number of unread emails?

    I don't believe that it is unread mails, but as yet I don't know what.
    I'll try to get a screen shot of the tab and ask in the Mint forum.

    I dual boot so I was in Windows for about 3 hours and when I returned, mine had a 3 on it.
    Sure enough I had 3 emails.

    Of course the bad part is, as soon as I clicked the panel icon and launched thunderbird
    the 3 went away. I didn't read any mail, just opened the program. Kinda of a clunky
    function IMHO.
    --
    Linux Mint 22.3, Mozilla Thunderbird 140.7.1esr, Mozilla Firefox 147.0.3
    Alan K.
    --- Synchronet 3.21b-Linux NewsLink 1.2
  • From Axel@none@not.here to alt.os.linux.mint on Sat Feb 14 11:46:01 2026
    From Newsgroup: alt.os.linux.mint

    Alan K. wrote:
    On 2/13/26 6:12 PM, Alan K. wrote:
    On 2/13/26 5:07 PM, Jeff Layman wrote:
    On 13/02/2026 14:32, Alan K wrote:
    On 2/13/2026 3:13 AM, Jeff Layman wrote:
    21.3 TB 140.7.1 esr

    Not sure if this is a Mint or Thunderbird question.

    A couple of times after starting TB it threw up a message that it
    hadn't been able to connect to a mail or news server. Fine. But on
    the Thunderbird tab in the taskbar
    (panel) there is a red circle with a 1 in it. I assume that is
    referring to a message of some sort. But where is it and how do I
    read it? The 1 in the red circle remained
    after I'd read and closed the message that TB showed at the start.

    Mint's logs show only one reference to TB and that is when it was
    started.

    I see that too, I just thought it was the number of unread emails?

    I don't believe that it is unread mails, but as yet I don't know what.
    I'll try to get a screen shot of the tab and ask in the Mint forum.

    I dual boot so I was in Windows for about 3 hours and when I
    returned, mine had a 3 on it.
    Sure enough I had 3 emails.

    Of course the bad part is, as soon as I clicked the panel icon and
    launched thunderbird the 3 went away.-a-a I didn't read any mail, just opened the program.-a-a Kinda of a clunky function IMHO.


    but the emails show as unread in TB
    --
    Linux Mint 22.3

    --- Synchronet 3.21b-Linux NewsLink 1.2
  • From Jeff Layman@Jeff@invalid.invalid to alt.os.linux.mint on Sat Feb 14 11:09:13 2026
    From Newsgroup: alt.os.linux.mint

    On 13/02/2026 23:13, Alan K. wrote:
    On 2/13/26 6:12 PM, Alan K. wrote:
    On 2/13/26 5:07 PM, Jeff Layman wrote:
    On 13/02/2026 14:32, Alan K wrote:
    On 2/13/2026 3:13 AM, Jeff Layman wrote:
    21.3 TB 140.7.1 esr

    Not sure if this is a Mint or Thunderbird question.

    A couple of times after starting TB it threw up a message that it hadn't been able to connect to a mail or news server. Fine. But on the Thunderbird tab in the taskbar
    (panel) there is a red circle with a 1 in it. I assume that is referring to a message of some sort. But where is it and how do I read it? The 1 in the red circle remained
    after I'd read and closed the message that TB showed at the start.

    Mint's logs show only one reference to TB and that is when it was started.

    I see that too, I just thought it was the number of unread emails?

    I don't believe that it is unread mails, but as yet I don't know what.
    I'll try to get a screen shot of the tab and ask in the Mint forum.

    I dual boot so I was in Windows for about 3 hours and when I returned, mine had a 3 on it.
    Sure enough I had 3 emails.

    Of course the bad part is, as soon as I clicked the panel icon and launched thunderbird
    the 3 went away. I didn't read any mail, just opened the program. Kinda of a clunky
    function IMHO.

    I closed TB and sent myself an email from a webmail account (from a
    different mailserver). I also sent a cc to another account on the
    webmail mailserver. After 15 minutes I restarted TB. There was nothing
    on the TB tab, but when I checked both messages had been received by
    their respective accounts and were showing in the folder pane inboxes.
    --
    Jeff
    --- Synchronet 3.21b-Linux NewsLink 1.2
  • From Paul@nospam@needed.invalid to alt.os.linux.mint on Sat Feb 14 09:33:49 2026
    From Newsgroup: alt.os.linux.mint

    On Fri, 2/13/2026 5:07 PM, Jeff Layman wrote:
    On 13/02/2026 14:32, Alan K wrote:
    On 2/13/2026 3:13 AM, Jeff Layman wrote:
    21.3 TB 140.7.1 esr

    Not sure if this is a Mint or Thunderbird question.

    A couple of times after starting TB it threw up a message that it hadn't been able to connect to a mail or news server. Fine. But on the Thunderbird tab in the taskbar
    (panel) there is a red circle with a 1 in it. I assume that is referring to a message of some sort. But where is it and how do I read it? The 1 in the red circle remained
    after I'd read and closed the message that TB showed at the start.

    Mint's logs show only one reference to TB and that is when it was started. >>>
    I see that too, I just thought it was the number of unread emails?

    I don't believe that it is unread mails, but as yet I don't know what. I'll try to get a screen shot of the tab and ask in the Mint forum.


    You set a "max connection limit" per server. The default
    may be two connections. These connections would run on
    their own thread. One connection can attempt to connect,
    and fail. It can print "I have failed" on the screen.
    Meanwhile, the connection limit is not exceeded, so a
    second thread runs. It could print "I have succeeded"
    but instead, it just gets your email :-)

    Any time you watch the status line on that software, it
    is bouncing around like a hula dancer. It's not doing
    that for fun, it's multiple threads messing with the
    display. That's why it's such a God awful mess.

    You could set the max connection limit to one thread if you want.
    Imagine how sane the status indicator will be. The
    order of progression in the left column, might actually appear
    linear. Like you were using someone elses client.

    Paul
    --- Synchronet 3.21b-Linux NewsLink 1.2
  • From Jeff Layman@Jeff@invalid.invalid to alt.os.linux.mint on Sun Feb 15 17:16:04 2026
    From Newsgroup: alt.os.linux.mint

    On 15/02/2026 17:09, Jeff Layman wrote:
    On 14/02/2026 14:33, Paul wrote:
    On Fri, 2/13/2026 5:07 PM, Jeff Layman wrote:
    On 13/02/2026 14:32, Alan K wrote:
    On 2/13/2026 3:13 AM, Jeff Layman wrote:
    21.3 TB 140.7.1 esr

    Not sure if this is a Mint or Thunderbird question.

    A couple of times after starting TB it threw up a message that it hadn't been able to connect to a mail or news server. Fine. But on the Thunderbird tab in the taskbar
    (panel) there is a red circle with a 1 in it. I assume that is referring to a message of some sort. But where is it and how do I read it? The 1 in the red circle remained
    after I'd read and closed the message that TB showed at the start.

    Mint's logs show only one reference to TB and that is when it was started.

    I see that too, I just thought it was the number of unread emails?

    I don't believe that it is unread mails, but as yet I don't know what. I'll try to get a screen shot of the tab and ask in the Mint forum.


    You set a "max connection limit" per server. The default
    may be two connections. These connections would run on
    their own thread. One connection can attempt to connect,
    and fail. It can print "I have failed" on the screen.
    Meanwhile, the connection limit is not exceeded, so a
    second thread runs. It could print "I have succeeded"
    but instead, it just gets your email :-)

    Any time you watch the status line on that software, it
    is bouncing around like a hula dancer. It's not doing
    that for fun, it's multiple threads messing with the
    display. That's why it's such a God awful mess.

    What software are you referring to? TB itself? I rarely see much on the status line except when I first start TB, manually check for new
    messages, or click on a message to download it.

    You could set the max connection limit to one thread if you want.
    Imagine how sane the status indicator will be. The
    order of progression in the left column, might actually appear
    linear. Like you were using someone elses client.

    After a few days without anything appearing, the TB tab finally showed a number a few minutes ago. I was able to get a cropped screenshot of it: <https://ibb.co/zWpWR2Wk>

    When I clicked on the tab the number immediately disappeared. I checked
    my email but there were *no* new messages in any of the four mail
    inboxes I have.

    There were some new messages on the two news servers I use, but there
    have been new messages for several days without the TB tab showing a number.

    It just appeared again after a "The connection was reset" box appeared.
    I think there was a fleeting box which appeared earlier today. That must
    be responsible for the number in the tab. I've just noticed that the tab
    for this new post message now also has a white No.1 in a red circle, as
    does the main TB tab.

    So does it represent an error message has appeared? If so, does that
    message reside anywhere in TB's logs once it has disappeared from the
    screen?
    --
    Jeff
    --- Synchronet 3.21b-Linux NewsLink 1.2
  • From Paul@nospam@needed.invalid to alt.os.linux.mint on Sun Feb 15 14:32:42 2026
    From Newsgroup: alt.os.linux.mint

    On Sun, 2/15/2026 12:16 PM, Jeff Layman wrote:
    On 15/02/2026 17:09, Jeff Layman wrote:
    On 14/02/2026 14:33, Paul wrote:
    On Fri, 2/13/2026 5:07 PM, Jeff Layman wrote:
    On 13/02/2026 14:32, Alan K wrote:
    On 2/13/2026 3:13 AM, Jeff Layman wrote:
    21.3 TB 140.7.1 esr

    Not sure if this is a Mint or Thunderbird question.

    A couple of times after starting TB it threw up a message that it hadn't been able to connect to a mail or news server. Fine. But on the Thunderbird tab in the taskbar
    (panel) there is a red circle with a 1 in it. I assume that is referring to a message of some sort. But where is it and how do I read it? The 1 in the red circle remained
    after I'd read and closed the message that TB showed at the start. >>>>>>
    Mint's logs show only one reference to TB and that is when it was started.

    I see that too, I just thought it was the number of unread emails?

    I don't believe that it is unread mails, but as yet I don't know what. I'll try to get a screen shot of the tab and ask in the Mint forum.


    You set a "max connection limit" per server. The default
    may be two connections. These connections would run on
    their own thread. One connection can attempt to connect,
    and fail. It can print "I have failed" on the screen.
    Meanwhile, the connection limit is not exceeded, so a
    second thread runs. It could print "I have succeeded"
    but instead, it just gets your email :-)

    Any time you watch the status line on that software, it
    is bouncing around like a hula dancer. It's not doing
    that for fun, it's multiple threads messing with the
    display. That's why it's such a God awful mess.

    What software are you referring to? TB itself? I rarely see much on the
    status line except when I first start TB, manually check for new
    messages, or click on a message to download it.

    You could set the max connection limit to one thread if you want.
    Imagine how sane the status indicator will be. The
    order of progression in the left column, might actually appear
    linear. Like you were using someone elses client.

    After a few days without anything appearing, the TB tab finally showed a
    number a few minutes ago. I was able to get a cropped screenshot of it:
    <https://ibb.co/zWpWR2Wk>

    When I clicked on the tab the number immediately disappeared. I checked
    my email but there were *no* new messages in any of the four mail
    inboxes I have.

    There were some new messages on the two news servers I use, but there
    have been new messages for several days without the TB tab showing a number.

    It just appeared again after a "The connection was reset" box appeared. I think there was a fleeting box which appeared earlier today. That must be responsible for the number in the tab. I've just noticed that the tab for this new post message now also has a white No.1 in a red circle, as does the main TB tab.

    So does it represent an error message has appeared? If so, does that message reside anywhere in TB's logs once it has disappeared from the screen?


    OK, what facility does the Linux platform have for Notifications ?

    And if one exists, did you turn Notifications off, forcing the icon
    to do the job with the "1" on it ?

    *******

    https://forums.linuxmint.com/viewtopic.php?t=434003

    "Try System Settings > Notifications > Enable notifications = off.

    That's how to do it if you use Cinnamon, anyway.
    "

    Try turning that ON, so the Thunderbird Notification will cause a popup of some sort.
    At a guess, you would still get an icon with a "1", but you should also get
    a more-informative dialog from the Notification.

    Actually, I think I saw a Notification in my test VM, but that's
    a VM with its own email server inside, and not appropriate for your
    situation. But I think when my test email server wasn't reachable,
    there was a Notification about it. Likely a TB140 or so.

    https://www.reddit.com/r/linuxmint/comments/18b0m3f/how_do_i_view_notification_history_on_linux_mint/

    "Well, in Mint Xfce there's a bell icon in the system tray by default
    which keeps a history (as well as lets you customize the position and theme
    of the notifications, also some control over which apps can show notifications - eg,
    I long ago stopped volume changes from popping up and clogging the log).
    No idea for Cinnamon or MATE.

    "That actually sounds like the same I have for Cinnamon at Mint 21.1 "

    Paul
    --- Synchronet 3.21b-Linux NewsLink 1.2
  • From Jeff Layman@Jeff@invalid.invalid to alt.os.linux.mint on Sun Feb 15 21:59:25 2026
    From Newsgroup: alt.os.linux.mint

    On 15/02/2026 19:32, Paul wrote:
    On Sun, 2/15/2026 12:16 PM, Jeff Layman wrote:
    On 15/02/2026 17:09, Jeff Layman wrote:
    On 14/02/2026 14:33, Paul wrote:
    On Fri, 2/13/2026 5:07 PM, Jeff Layman wrote:
    On 13/02/2026 14:32, Alan K wrote:
    On 2/13/2026 3:13 AM, Jeff Layman wrote:
    21.3 TB 140.7.1 esr

    Not sure if this is a Mint or Thunderbird question.

    A couple of times after starting TB it threw up a message that it hadn't been able to connect to a mail or news server. Fine. But on the Thunderbird tab in the taskbar
    (panel) there is a red circle with a 1 in it. I assume that is referring to a message of some sort. But where is it and how do I read it? The 1 in the red circle remained
    after I'd read and closed the message that TB showed at the start. >>>>>>>
    Mint's logs show only one reference to TB and that is when it was started.

    I see that too, I just thought it was the number of unread emails?

    I don't believe that it is unread mails, but as yet I don't know what. I'll try to get a screen shot of the tab and ask in the Mint forum.


    You set a "max connection limit" per server. The default
    may be two connections. These connections would run on
    their own thread. One connection can attempt to connect,
    and fail. It can print "I have failed" on the screen.
    Meanwhile, the connection limit is not exceeded, so a
    second thread runs. It could print "I have succeeded"
    but instead, it just gets your email :-)

    Any time you watch the status line on that software, it
    is bouncing around like a hula dancer. It's not doing
    that for fun, it's multiple threads messing with the
    display. That's why it's such a God awful mess.

    What software are you referring to? TB itself? I rarely see much on the
    status line except when I first start TB, manually check for new
    messages, or click on a message to download it.

    You could set the max connection limit to one thread if you want.
    Imagine how sane the status indicator will be. The
    order of progression in the left column, might actually appear
    linear. Like you were using someone elses client.

    After a few days without anything appearing, the TB tab finally showed a >>> number a few minutes ago. I was able to get a cropped screenshot of it:
    <https://ibb.co/zWpWR2Wk>

    When I clicked on the tab the number immediately disappeared. I checked
    my email but there were *no* new messages in any of the four mail
    inboxes I have.

    There were some new messages on the two news servers I use, but there
    have been new messages for several days without the TB tab showing a number.

    It just appeared again after a "The connection was reset" box appeared. I think there was a fleeting box which appeared earlier today. That must be responsible for the number in the tab. I've just noticed that the tab for this new post message now also has a white No.1 in a red circle, as does the main TB tab.

    So does it represent an error message has appeared? If so, does that message reside anywhere in TB's logs once it has disappeared from the screen?


    OK, what facility does the Linux platform have for Notifications ?

    And if one exists, did you turn Notifications off, forcing the icon
    to do the job with the "1" on it ?

    *******

    https://forums.linuxmint.com/viewtopic.php?t=434003

    "Try System Settings > Notifications > Enable notifications = off.

    That's how to do it if you use Cinnamon, anyway.
    "

    Try turning that ON, so the Thunderbird Notification will cause a popup of some sort.
    At a guess, you would still get an icon with a "1", but you should also get
    a more-informative dialog from the Notification.

    I've always had notifications enabled as I find them useful. However,
    I'll disable them for a week or so to see if the TB tab number
    disappears too. I guess that I could ask a question in the LM forum to
    see if anyone recognises a TB tab with a number in it.

    Actually, I think I saw a Notification in my test VM, but that's
    a VM with its own email server inside, and not appropriate for your situation. But I think when my test email server wasn't reachable,
    there was a Notification about it. Likely a TB140 or so.

    https://www.reddit.com/r/linuxmint/comments/18b0m3f/how_do_i_view_notification_history_on_linux_mint/

    "Well, in Mint Xfce there's a bell icon in the system tray by default
    which keeps a history (as well as lets you customize the position and theme
    of the notifications, also some control over which apps can show notifications - eg,
    I long ago stopped volume changes from popping up and clogging the log).
    No idea for Cinnamon or MATE.

    "That actually sounds like the same I have for Cinnamon at Mint 21.1 "

    I seem to remember there's a icon of some sort which appears in the
    panel when there's a notification (eg an update or upgrade to mint itself).
    --
    Jeff
    --- Synchronet 3.21b-Linux NewsLink 1.2
  • From Jeff Layman@jeff@invalid.invalid to alt.os.linux.mint on Tue Feb 24 10:06:53 2026
    From Newsgroup: alt.os.linux.mint

    On 15/02/2026 21:59, Jeff Layman wrote:
    On 15/02/2026 19:32, Paul wrote:
    On Sun, 2/15/2026 12:16 PM, Jeff Layman wrote:
    On 15/02/2026 17:09, Jeff Layman wrote:
    On 14/02/2026 14:33, Paul wrote:
    On Fri, 2/13/2026 5:07 PM, Jeff Layman wrote:
    On 13/02/2026 14:32, Alan K wrote:
    On 2/13/2026 3:13 AM, Jeff Layman wrote:
    21.3 TB 140.7.1 esr

    Not sure if this is a Mint or Thunderbird question.

    A couple of times after starting TB it threw up a message that it hadn't been able to connect to a mail or news server. Fine. But on the Thunderbird tab in the taskbar
    (panel) there is a red circle with a 1 in it. I assume that is referring to a message of some sort. But where is it and how do I read it? The 1 in the red circle remained
    after I'd read and closed the message that TB showed at the start. >>>>>>>>
    Mint's logs show only one reference to TB and that is when it was started.

    I see that too, I just thought it was the number of unread emails? >>>>>>
    I don't believe that it is unread mails, but as yet I don't know what. I'll try to get a screen shot of the tab and ask in the Mint forum.


    You set a "max connection limit" per server. The default
    may be two connections. These connections would run on
    their own thread. One connection can attempt to connect,
    and fail. It can print "I have failed" on the screen.
    Meanwhile, the connection limit is not exceeded, so a
    second thread runs. It could print "I have succeeded"
    but instead, it just gets your email :-)

    Any time you watch the status line on that software, it
    is bouncing around like a hula dancer. It's not doing
    that for fun, it's multiple threads messing with the
    display. That's why it's such a God awful mess.

    What software are you referring to? TB itself? I rarely see much on the >>>> status line except when I first start TB, manually check for new
    messages, or click on a message to download it.

    You could set the max connection limit to one thread if you want.
    Imagine how sane the status indicator will be. The
    order of progression in the left column, might actually appear
    linear. Like you were using someone elses client.

    After a few days without anything appearing, the TB tab finally showed a >>>> number a few minutes ago. I was able to get a cropped screenshot of it: >>>> <https://ibb.co/zWpWR2Wk>

    When I clicked on the tab the number immediately disappeared. I checked >>>> my email but there were *no* new messages in any of the four mail
    inboxes I have.

    There were some new messages on the two news servers I use, but there
    have been new messages for several days without the TB tab showing a number.

    It just appeared again after a "The connection was reset" box appeared. I think there was a fleeting box which appeared earlier today. That must be responsible for the number in the tab. I've just noticed that the tab for this new post message now also has a white No.1 in a red circle, as does the main TB tab.

    So does it represent an error message has appeared? If so, does that message reside anywhere in TB's logs once it has disappeared from the screen?


    OK, what facility does the Linux platform have for Notifications ?

    And if one exists, did you turn Notifications off, forcing the icon
    to do the job with the "1" on it ?

    *******

    https://forums.linuxmint.com/viewtopic.php?t=434003

    "Try System Settings > Notifications > Enable notifications = off.

    That's how to do it if you use Cinnamon, anyway.
    "

    Try turning that ON, so the Thunderbird Notification will cause a popup of some sort.
    At a guess, you would still get an icon with a "1", but you should also get >> a more-informative dialog from the Notification.

    I've always had notifications enabled as I find them useful. However,
    I'll disable them for a week or so to see if the TB tab number
    disappears too. I guess that I could ask a question in the LM forum to
    see if anyone recognises a TB tab with a number in it.

    I disabled notifications for a week and saw no sign of a number in the
    TB tab. I reactivated them yesterday and a number in the TB tab
    reappeared this morning. It wasn't, however, associated in any way with
    TB - the notification was simply a message that it was safe to unplug a
    USB stick. As soon as I'd read the message and pulled the stick the
    number in the TB tab disappeared. See comment at end of this post.

    Actually, I think I saw a Notification in my test VM, but that's
    a VM with its own email server inside, and not appropriate for your
    situation. But I think when my test email server wasn't reachable,
    there was a Notification about it. Likely a TB140 or so.

    https://www.reddit.com/r/linuxmint/comments/18b0m3f/how_do_i_view_notification_history_on_linux_mint/

    "Well, in Mint Xfce there's a bell icon in the system tray by default >> which keeps a history (as well as lets you customize the position and theme
    of the notifications, also some control over which apps can show notifications - eg,
    I long ago stopped volume changes from popping up and clogging the log).
    No idea for Cinnamon or MATE.

    "That actually sounds like the same I have for Cinnamon at Mint 21.1 "

    I seem to remember there's a icon of some sort which appears in the
    panel when there's a notification (eg an update or upgrade to mint itself).

    It was clicking on that icon which showed the message about the USB stick.
    --
    Jeff
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