Pedestrian traffic is regulated by
§25 and
§26 StVO, and mostly codifies what one would consider common sense. Cross the bloody road in a straight line, don't bumble about, don't run head-first into full traffic. Pedestrians crossing a red light may be fined 5€, or 10€ if their malovelent street-crossing rampage causes any damage to property. I'm not even kidding. See
BKatV, Lfd. Nr. 130ff. Of course that's in German only, sorry.
To sum things up: There is no regulation explicitly prohibiting jaywalking, but there is a 5€ fine for crossing a red light as a pedestrian. There is no "acceptable distance of a traffic light" known to me which would require you by law to use it instead of just crossing the road. You may never cross a road if you have to step over/under any chains or other objects blocking access to the road. Those are there for a reason.
On the way from the train station/overflow hotel, there's a large-ish road to cross (the Otto-von-Guericke-Str.), with traffic lights being only a few dozen meters off. It is rather common to cross this road "jaywalking style", and relatively safe to do so. All the cool kids are doing it.
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An overzealous cop MAY approach you for a lecture, though, if he considers the traffic lights down the road to be "close enough", though. If you want to take this to court, feel free, otherwise just stick to walking the ~30m extra to the nearest crossing, and feel good about yourself doing the right thing.
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