Solve the riddle based on the topic matter:
 
They named me a cloudy blend. I’m not so clear, yet not so strong.

If I sit still for long enough, my contents part ways, like friends after a short trip.

Shine a light through me, and you’ll see it dance, not too wild, but enough to notice.

Bring out the filter, and I’ll get caught; I never could pass quietly.
 
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