On Firefox:
console.log(document.createElement('input').placeholder === ''); // true
console.log(document.createElement('input').hasOwnProperty('placeholder')); // false
I think the 2nd line codes should return true just like what you can see on Chrome. But I get false. Why?
Thank you!
The spec defines the JS property as being on the prototype, not on the object itself. Chrome gets this wrong for all DOM properties; it’s a longstanding bug in Chrome.