If I go to Settings -> Appearance -> Message List -> Default aggregation -> Configure and add a new Aggregation Mode with any name and settings, it is not shown in the Default aggregation combobox until KMail is restarted.
Oh ! I will investigate it this night or tomorrow morning. Thanks for bug report
Git commit cb41513c0f76181caed92bf868766c4397e8a53a by Laurent Montel. Committed on 06/03/2023 at 21:10. Pushed by mlaurent into branch 'master'. Fix 466931: Custom Message Aggregation Modes are not shown in Message List preferences until restart FIXED-IN: 5.23.0 M +1 -1 messagelist/src/utils/configureaggregationsdialog.cpp M +1 -1 messagelist/src/utils/configurethemesdialog.cpp https://invent.kde.org/pim/messagelib/commit/cb41513c0f76181caed92bf868766c4397e8a53a
Thanks for the fix! Do you plan on backporting it?
nope as there is not new 22.12.x