Major deserialization issue in release/20.12 git branch

[David Faure]

Hi Dan,

All my calendars (caldav) and todos (icaldir) disappeared, after updating stable branch (release/20.12) and rebooting.

org.kde.pim.akonadicore: WARNING: Akonadi::ItemSerializer::deserialize(Akonadi::Item&, const QByteArray&, QIODevice&, int)::<lambda Unable to deserialize payload part: "RFC822" in item 1650947 collection 1930
org.kde.pim.akonadicore: WARNING: Akonadi::ItemSerializer::deserialize(Akonadi::Item&, const QByteArray&, QIODevice&, int)::<lambda  payload data was:  "\xCA\x1C\x01.\x00\x00\x00\x01..."
CRITICAL: KCalendarCore::ICalFormat::readIncidence|?libQt5Core.so.5?|qt_message_output parse error from icalcomponent_new_from_string. string= "Ê\u001C\u0001."
org.kde.pim.calendar_serializer: WARNING: Akonadi::SerializerPluginKCalCore::deserialize Failed to parse incidence! Item id =  1650946 Storage collection id  1930 parentCollectionId =  1930
org.kde.pim.calendar_serializer: WARNING: Akonadi::SerializerPluginKCalCore::deserialize "?\u001C\u0001."

Volker showed me some commits related to LZMA compression, but commit 53d1b4c63189 says this is disabled in 20.12.

Could it be that because I was using an earlier version of release/20.12, my akonadi incidences actually got LZMA-compressed,
and now there's no code available to uncompress them?

-- 
David Faure, faure at kde.org, http://www.davidfaure.fr
Working on KDE Frameworks 5