This is actually a very old issue, and it's sort of a LW/Ami issue, but not really.
Sometimes, BB traces will appear that just aren't markable. It has to do with the thresholds set in the sim. LW/Ami increased the BB sensititivy of the spherical array. Is it turned out, this also increased the gap between the visual threshold and the markable threshold, which means that the bug occurs more with LW/Ami than it does with stock DW.
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