PS
available tasks is an element of a
context (yields a filtered list for tasks of that context).
If you wanted to bypass the context route, you might have to add the
flagged condition to the end of something like this :-)
(blocked is false) and (completed is false) and ((start date is missing value) or (start date < now)) and ((its containing project is missing value) or (status of its containing project is active) and ((start date of its containing project < now) or (start date of its containing project is missing value))) and ((its context is missing value) or ((allows next action of its context is true) and (hidden of its context is false)))
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