Dear Maintainer,

after upgrading thunderbird to 1:115.1.0-1, it has become unusable.

starting works nicely and i get the password prompt, after which the
main screen is shown.

however, the window is totally unresponsive, and thunderbird works
happily at 100% for hours.

my system is not super-new, but not that old either:
```
$ lscpu
Architecture:            x86_64
  CPU op-mode(s):        32-bit, 64-bit
  Address sizes:         39 bits physical, 48 bits virtual
  Byte Order:            Little Endian
CPU(s):                  8
  On-line CPU(s) list:   0-7
Vendor ID:               GenuineIntel
  Model name:            Intel(R) Core(TM) i7-7700 CPU @ 3.60GHz
    CPU family:          6
    Model:               158
    Thread(s) per core:  2
    Core(s) per socket:  4
    Socket(s):           1
    Stepping:            9
    CPU(s) scaling MHz:  50%
    CPU max MHz:         4200.0000
    CPU min MHz:         800.0000
    BogoMIPS:            7200.00
[...]

$ cat /proc/meminfo
MemTotal:       32783544 kB
[...]

$ lspci | grep -i nvidia
01:00.0 VGA compatible controller: NVIDIA Corporation GP104 [GeForce GTX 1080] (rev a1)
[...]

$ df -h
Filesystem      Size  Used Avail Use% Mounted on
/dev/nvme0n1p2  202G  183G  9.2G  96% /
[...]

$
```

As you can see i'm slightly tight on disk space (and my ~/.thunderbird/
folder takes about 5.2GB), but i *think* this should be a usable setup.

of course, thunderbird_115 upgraded my profile, so i can no longer
downgrade to the thunderbird from bookworm :-(

dfmasr
IOhannes

Hello IOhannes,

Am 09.08.23 um 17:24 schrieb IOhannes m zmölnig (Debian/GNU):

this isn't normal for sure. But there can be various reasons why TB is
eaten all available CPU power. In quite all the cases I've encountered
the profile was the reason for this.

You might have seen and tried some options you have seen on the Debian
wiki page, if not please keep an eye on it.

The mainly two main points to debug the situation are to run the JS
console if possible and to start up with a clean profile if no reason
and solution can be found in the JS log console.

Sorry, I haven't more useful tips.

...

There is the option '--allow-downgrade' which works quite acceptable in
recent days in case you need to start with an older version.

Hi,

I' having the same issue as the reporter on all of the machines I am
responsible for. Also none of the tips in
https://wiki.debian.org/Thunderbird#Bug_Reporting_.2F_Issues are helping
on any of those machines.
Perhaps I have some additional to be able to identify how to solve this:
I am using only IMAP Accounts. On one PC I tried to setup a new profile.
Right after just having configured the first account, the behavior was
identical to my existing profile, TB was unresponsive most of the time.
In the General-Settings I changed the format to "File per message
(maildir)", removed the account and recreated it.
Though the usage ("top") also seems very high, TB "feels" responsive.
What I have not done so far:
  * Added my other accounts
  * Added any Address book (I'm using multiple CardDAV books)
  * Added any Calendar (I'm using multiple CalDAV-Calendars and one
    readonly ICS file)

Therefore I see a chance that converting all mailboxes to maildir format
might solve this issue.
As a first step, it would be good if someone else could either falsify
my assumption or confirm this is also helping in a second scenario.
If this can be confirmed, the next step would be to "migrate" accounts
from mbox to maildir format.
The main problem I see is, that I don't know a way to convert an
existing account in TB from mbox to maildir format. I read something
about an experimental setting (mail.store_conversion_enabled) but I have
no experience with this (yet?).

Regards
Armin

P.S.: Having to convert all profiles on all machines manually is not
acceptable, I don't even want to estimate how long this might take.