Fix problems with latest jquery

app/assets/javascripts/active_admin/select2.js

@@ -0,0 +1,3 @@
+//= require select2
+
+//= require_tree ./select2

app/assets/javascripts/active_admin/select2/select2.js

@@ -0,0 +1,30 @@
+'use strict';
+var initSelect2;
+
+initSelect2 = function(inputs, extra = {}) {
+  return inputs.each(function() {
+    var item, options;
+    item = $(this);
+    // reading from data allows <input data-select2='{"tags": ['some']}'> to be passed to select2
+    options = $.extend({
+      allowClear: true
+    }, extra, item.data('select2'));
+    // because select2 reads from input.data to check if it is select2 already
+    item.data('select2', null);
+    return item.select2(options);
+  });
+};
+
+$(document).on('has_many_add:after', '.has_many_container', function(e, fieldset) {
+  return initSelect2(fieldset.find('.select2-input'));
+});
+
+$(document).on('page:change page:load turbolinks:load', function() {
+  initSelect2($(".select2-input"), { placeholder: ""
+  });
+});
+
+$(document).ready(function() {
+  initSelect2($(".select2-input"), { placeholder: "" });
+});
+