Tasks created in Marvin are synced to your calendar when all of the following conditions are met:

a. your calendar was setup with a linked category and/or label (this can be setup when you first link a calendar in the calendar sync strategy settings - unlink and re-add the calendar if you first added it with neither label nor category and want two-way sync)
b. the task has that label/category
c. the task is scheduled
d. the task has a time in its title (tasks that you create in Marvin's calendar or drag into Marvin's agenda automatically have a time in the title even though it is hidden sometimes)

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