SyntaxError: for-in loop head declarations may not have initializers

SyntaxError: for-in loop head declarations cannot have an initializer (Edge)
SyntaxError: for-in loop head declarations may not have initializers (Firefox)
SyntaxError: for-in loop variable declaration may not have an initializer. (Chrome)

const obj = { a: 1, b: 2, c: 3 };
for (const i = 0 in obj) {
  console.log(obj[i]);
}
// SyntaxError: for-in loop head declarations may not have initializers

"use strict";
var obj = { a: 1, b: 2, c: 3 };
for (var i in obj) {
  console.log(obj[i]);
}

var arr = ["a", "b", "c"];
for (var i = 2; i < arr.length; i++) {
  console.log(arr[i]);
}
// "c"