Duplicate field properties before modifying them

issue11087
review381571004

src/screen.js

@@ -1758,7 +1758,9 @@
                 if (props.selection instanceof Array) {
                     continue;
                 }
+                props = jQuery.extend({}, props);
                 props.selection = this.get_selection(props);
+                fields[name] = props;
             }
 
             if ('arch' in view_tree) {