Create a dedicated class / selector and add visual emphasis to statements that violate constraints, to incentivize manual curation of data quality issues. See a possible example below:
Description
Description
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The class would be for the statement group?
@Lucas_Werkmeister_WMDE how difficult would that be?
Comment Actions
Hopefully not too difficult, though it might get trickier when the interface changes as you enter and exit edit mode. (We might as well add classes on both the statement group and the individual statement, IMHO – I don’t think one would be much more difficult than the other, and then editors can decide which one they want to style.)