The "official" Unicode Regular Expressions (UTS #18) document, dated February 8, 2022, has never been updated since then, and the four new Unicode properties introduced in Unicode 15.1 are only listed in the Proposed Update *draft*, dated May 11, 2023...
This could explain why #Safari, #Firefox, and the #Electron framework (#Chromium) trigger an "invalid property" error for the /\p{IDS_Unary_Operator}/u #regex in JavaScript, while /\p{IDS_Binary_Operator}/u is ok...








