[SOGo] Can't save a Task in Calendar without from/due date

Hello, I've recently updated to SOGo v4.0.1 and since then am unable to save Tasks without from/due date. Save-Button turns from light blue to grey but nothing else happens. No 'saveAsTask' loglines. Anyone else have this problem? Bug description is like here but not fixed. OS is Ubuntu 18.04. h

[SOGo] BTS activities for Tuesday, August 14 2018

Title: BTS activities for Tuesday, August 14 2018 BTS Activities Home page: http://www.sogo.nu/bugs Project: SOGo For the period covering: Tuesday, August 14 2018 idlast updatestatus (resolution)categorysummary