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It's not about whether this feature is easy or hard to add. It's about 
getting things done right in the first place and in the right order. I 
could tack on a sleep timer in virtually no time, but it'd raise 
problems with new concepts in future versions that I really want to 
avoid. The pre-condition to adding a sleep timer in the way I think it 
should be implemented simply aren't met yet. When they are met, it 
will be added.
I generally don't give any timeframes except for fixes of showstopping 
bugs/problems.
Best regards, 
Felix Schwarz