After using Math.ceil, one value was rounded up to 50 and the other to 80.
However, when I added these two values together, the result unexpectedly turned out to be 131.
console.log(Math.ceil(e.currentTarget.clientHeight) // 50
console.log(Math.ceil(e.currentTarget.scrollTop)) // 80
console.log(Math.ceil(e.currentTarget.clientHeight) + Math.ceil(e.currentTarget.scrollTop)); // 131
Status of the implementation
e.currentTarget.clientHeight // 50
e.currentTarget.scrollTop // 80.1111145019531