User:Ainz Ooal Gown/rollbacksummary.js

Note: After saving, you have to bypass your browser's cache to see the changes. Internet Explorer: press Ctrl-F5, Mozilla: hold down Shift while clicking Reload (or press Ctrl-Shift-R), Opera/Konqueror: press F5, Safari: hold down Shift + Alt while clicking Reload, Chrome: hold down Shift while clicking Reload.

Documentation for this user script can be added at User:Ainz Ooal Gown/rollbacksummary.

if (document.getElementsByClassName('mw-rollback-link')[0].getElementsByTagName('a')) {
mw.loader.using(['oojs-ui-windows', 'oojs-ui-core', 'oojs-ui.styles.icons-editing-core']).then( function () {
var promptSummary = function(e) {
	e.preventDefault();
var rollbacklink = this.href;
	OO.ui.prompt( 'Are you sure you want to rollback latest edits made to this page by this user?', { textInput: { placeholder: 'Edit summary (optional)' } } ).done( function ( result ) {
var rollbacksummaryadd = rollbacklink + '&summary=' + result ;
		if ( result !== null ) {		
location.href = rollbacksummaryadd;
		}
});
};
if (mw.config.get('skin') === "minerva") {
  $('.mw-rollback-link a').addClass(['mw-ui-button','mw-ui-destructive']).click(promptSummary);
}
else {
$('.mw-rollback-link a').click(promptSummary);
}
    });
}