commit 7c408e05ad361ec70e50452bbcc0edd1e23e5755
Author: Tamás Brückner <tamas.bruckner@integralvision.hu>
Date:   Thu Mar 1 17:23:42 2018 +0100

    Fix multiple handler attachment.

diff --git a/enhancers/multiselect/js/entity_browser_enhanced.multiselect.js b/enhancers/multiselect/js/entity_browser_enhanced.multiselect.js
index 5a7d23b..da10299 100755
--- a/enhancers/multiselect/js/entity_browser_enhanced.multiselect.js
+++ b/enhancers/multiselect/js/entity_browser_enhanced.multiselect.js
@@ -20,9 +20,11 @@
       // Reset the selected entities counter to 0.
       var selectedEntities = 0;
 
-      // When we click on a selectable entity.
-      $('form.entity-browser-enhanced.multiselect .view .views-col', context).on('click', function () {
+      var $columns =  $('form.entity-browser-enhanced.multiselect .view .views-col').filter(':not(.entity-browser-enhanced-processed)');
+      $columns.addClass('entity-browser-enhanced-processed');
 
+      // When we click on a selectable entity.
+      $columns.on('click', function () {
         // If the cardinality for the validation is more than 1.
         if (drupalSettings.entity_browser_enhanced.multiselect.cardinality > 1) {
           if ($(this).hasClass("selected")) {
@@ -68,8 +70,7 @@
       });
 
       // When we double click on a selectable entity.
-      $('form.entity-browser-enhanced.multiselect .view .views-col').on('dblclick', function () {
-
+      $columns.on('dblclick', function () {
         // Select the current clicked entity.
         $(this).addClass('selected').find(input).prop('checked', true);
         // Unselect everything else.