Sync source gets deselected

[wKovacs]

Your environment

Ubuntu 23.10 with KDE
Syncing Office 365 calendar

TbSync version: 4.8
Thunderbird version: Betterbird 115.9.0-bb26 (64-bit) (but same problem with Thunderbird)

Expected behavior

Selected sync source stays selected

Actual behavior

Every few days the check mark before the calendar disappears an I have to select it again

Steps to reproduce

Setup an office 365 calendar for sync
wait a few days
check tbsync

[tantive-nessi]

Similar issue here (or maybe the same).
The account remains in the list, but all "Avaliable Resources" are deselected, so the calendar vanishes from the list of calendars in TB. I have to re-enable the calendar of the account, trigger the initial sync and then the calendar reappears with all the settings (e.g. color) in TB.

Environment

Windows 11
TB 115.10.1
TbSync 4.8

[ohmer1]

Same issue too with M365 calendars.

Ubuntu 22.04
Thunderbird 115.11.0
TbSync 4.8

[maehne]

I am observing the same issue with Microsoft 365 calendars and contacts on an up-to-date Arch Linux x86_64 installation with Thunderbird 115.10.2 (64-Bit) and TbSync 4.8.

[simonflutilliant]

Same issue here. Seems to be linked with loosing connections.