I find it bizarre that Array.Find(...) method only finds the first matched entry rather than all matching entries. Coming from other languages such as C#, Java, JS, etc. where the find method (called filter) produces a list/array of found entries, I find this behaviour is not what I would've expected if my array has duplicates.
Now sure, I could simply write a custom function using the for loop and iterate through the array to find all matching values, but shouldn't this be the default though?
var array = [1,2,3,2,5,2,1]
result indices: array, array, array
result indices: array