Question

Which is not a Mozilla CSS Extension?

(a) ::-webkit-input-placeholder

(b) :-moz-placeholder

(c) –moz-ui-valid

(d) :-moz-submit-invalid

I had been asked this question in an interview for job.

The question is from Appearance of Form Elements in section Lists, Tables and Forms of CSS

Answer 1

Correct option is (a) ::-webkit-input-placeholder

To explain: Mozilla CSS Extensions include :-moz-placeholder, :-moz-ui-invalid, :moz-ui-valid, :moz-submit-invalid. ::-webkit-input-placeholder is Webkit CSS Extension, :-ms-input-placeholder is Microsoft CSS Extension.