Google tasks are all-day tasks
In the current Google tasks api https://developers.google.com/tasks/reference/rest/v1/tasks#Task the "due" field only contains date information; the time portion is fixed at 00:00 UTC. Treating it as a meaningful UTC date-time causes KOrganizer to display the task at an arbitrary time, and probably on the wrong day. Treating Google tasks as all-day tasks works around the problem.
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