This feature is non-standard and is not on a standards track. Do not use it on production sites facing the Web: it will not work for every user. There may also be large incompatibilities between implementations and the behavior may change in the future.
::-webkit-search-cancel-button CSS pseudo-element represents a button (the "cancel button") at the edge of an
type="search" which clears away the current value of the
<input> element. This button and pseudo-element are non-standard, supported only in WebKit and Blink, hence the vendor prefix. The clear button is only shown on non-empty search
Not part of any standard.