Exodus 18:26 (minor modif. to Sefaria English):
וְשָׁפְט֥וּ אֶת־הָעָ֖ם בְּכָל־עֵ֑ת אֶת־הַדָּבָ֤ר הַקָּשֶׁה֙ יְבִיא֣וּן אֶל־מֹשֶׁ֔ה וְכָל־הַדָּבָ֥ר הַקָּטֹ֖ן יִשְׁפּוּט֥וּ הֵֽם׃
And they judged the people at all times: the hard matters they brought to Moses, and every small matter they judged themselves.
I was curious about the "strange" usage of the verb יִשְׁפּוּט֥וּ using the shuruq. I find an explanation by Shada"l, but I don't really understand what he's saying.
I'd appreciate if someone can summarize the main points. I don't need a literal translation.