Currently,
fff_failed gets marked for 'already have x chapters' and 'site is not newer' errors. I'd like to have error'd books get marked but skip the no-updates. Would it be much work to have a 'for all errors' option like the one for the error column?
Additionally: AO3 stories put into a hidden collection get a 'NoneType' error. It might make sense to have a unique error for this.
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