The 'stalled' filter for contexts is currently described in the help file by four words: "contexts without any actions"

This might well suggest something like 'contexts where number of tasks is 0' but its actual behaviour seems to be closer to:

contexts where available task count is 0 and allows next action is true and hidden is false

So for the help file, I might suggest something like:

"Contexts which are neither on hold nor dropped, but have no available tasks."

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