On the standards track: Yes
Is Experimental: No
Is Deprecated: No
In Chrome version 1 on 2008-12-11 Note: border-radius on <select> elements is ignored unless -webkit-appearance is overridden to an appropriate value.
In Chrome Android version 18 on 2012-06-27 Note: border-radius on <select> elements is ignored unless -webkit-appearance is overridden to an appropriate value.
In Edge version 12 on 2015-07-29
In Firefox version 1 on 2004-11-09 Note: Historically, Firefox has allowed keyboard and mouse events to bubble up from the <option> element to the parent <select> element, although this behavior is inconsistent across many browsers. For better Web compatibility (and for technical reasons), when Firefox is in multi-process mode the <select> element is displayed as a drop-down list. The behavior is unchanged if the <select> is presented inline and it has either the multiple attribute defined or a size attribute set to more than 1. Rather than watching <option> elements for events, you should watch for change events on <select>. See bug 1090602 for details.
In Firefox for Android version 4 on 2011-03-29 Note: Firefox for Android, by default, sets a background-image gradient on all <select multiple> elements. This can be disabled using background-image: none.
In Internet Explorer version ≤11 on undefined
In Quest Browser version 5.0 on undefined Note: border-radius on <select> elements is ignored unless -webkit-appearance is overridden to an appropriate value.
In Opera version 2 on 1996-07-14
In Opera Android version 10.1 on 2010-11-09
In Safari version 1 on 2003-06-23 Note: border-radius on <select> elements is ignored unless -webkit-appearance is overridden to an appropriate value.
In Safari on iOS version 1 on 2007-06-29 Note: border-radius on <select> elements is ignored unless -webkit-appearance is overridden to an appropriate value.
In Samsung Internet version 1.0 on 2013-04-27 Note: border-radius on <select> elements is ignored unless -webkit-appearance is overridden to an appropriate value.
In WebView Android version 4.4 on 2013-12-09 Note: border-radius on <select> elements is ignored unless -webkit-appearance is overridden to an appropriate value.
In WebView on iOS version 1 on 2007-06-29 Note: border-radius on <select> elements is ignored unless -webkit-appearance is overridden to an appropriate value.