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You know... it's really, really frustrating to have someone just constantly asking for more and more and more and never even bothering to say "thanks".
As a note, the indicator isn't gone... it's actually quite visible still - and the suggested edits queue (if I remember correctly) is the queue with the smallest number of items needed to turn the indicator on (and red). :) The numbers in the dot are gone, though - because they were nearly always incorrect, which people constantly complained about. :P
It's hard to have people you respect disappear, so I understand your concern. I remember one of the mods on Cooking disappearing completely for a year and no one was able to contact them. One thing that might help is to focus less on their activity stats and focus more on "I noticed that one of our really active mods hasn't been here for a while, are they OK?" And this may be a better question for chat rather than meta. :)
