The Xirmisala population collection law, "Dust Dowsing"—which reportedly provides +30% Dust on systems with a Unique Planet—has no effect.

In addition to the law's effect description reading, "LawEffectP00L26-PopulationCollectionMinorOracularEffectOverride" instead of an actual modifier (the +30% Dust on Unique Planet is information I found online while looking for a solution), the reported modifier of +30% doesn't take effect. Having this law active provides no bonus to a system's Dust income nor a unique planet's Dust output. As near as I can tell, the law does literally nothing.

In searching the XMLs for a way to fix the issue, I found that the "SimulationDescriptors[LawEffect_DLC4]" file has no actual law effect described in it. It seems to name the law effect, but then doesn't actually provide an effect. I don't know if this is the source of the issue, but I'm not very proficient in modding anyway, so I wasn't able to make it work with the few things I tried. All I can say for sure is, the Xirmisala law simply doesn't do anything.