Odd indeed. I’ll clean it out this weekend but will take a pic once more skimmate accumulates are the top of the cup.Neck size needs to be right. Sounds like you could either get a skimmer that’s the right size or try an auto neck cleaner.
Doesn’t make sense to me that you would get dark thick skimmate stuck to the neck but only tea in the cup.
This should still be exporting wastes as long as you clean the neck often.
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