Plugins are loaded *once*, but torn-down/instantiated multiple times,
and sometimes in the reverse order.
As such, if we use a public function member as the scheduled task, we're
always pointing to the same function, and going from FM to RD
effectively *un*schedules it.
Instead, use an instance-specific closure, so that each instance
schedules & unschedules don't affect each other.
In the same vein, settings ought to be read at instantiation, not at
loading, otherwise, changing a setting in the FM, then switching to the
reader will not pick up the changes.
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