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Go to your Calendar, then select Quick filters > Manage quick filters.
Create quick filters, for example, as described in the table above, or create your own.
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Options:
Join type: You can choose how the filters will behave when 2 or more filter conditions are selected.
AND - Check this option if you want to extend your filter. For example, show issues labeled test and labeled test 2 at the same time.
OR - This filter will expand your selection. For example, if you want to see tasks with critical priority and tasks with blocking priority on the same calendar.