check that drop exists

via HubSpot#171

bower.json

@@ -1,6 +1,6 @@
 {
   "name": "tether-drop",
-  "version": "1.4.2",
+  "version": "1.4.3",
   "homepage": "https://github.com/HubSpot/drop",
   "authors": [
     "Adam Schwartz <[email protected]>",

dist/js/drop.js

@@ -1,4 +1,4 @@
-/*! tether-drop 1.4.1 */
+/*! tether-drop 1.4.3 */
 
 (function(root, factory) {
   if (typeof define === 'function' && define.amd) {
@@ -420,6 +420,12 @@ function createContext() {
           return;
         }
 
+        // via https://github.com/HubSpot/drop/pull/171
+        if (!this.drop) {
+          // The instance was destroyed
+          return;
+        }
+
         if (!this.drop.parentNode) {
           document.body.appendChild(this.drop);
         }

package.json

@@ -1,6 +1,6 @@
 {
   "name": "tether-drop",
-  "version": "1.4.2",
+  "version": "1.4.3",
   "description": "Client-side library for creating dropdowns",
   "authors": [
     "Zack Bloom <[email protected]>",

src/js/drop.js

@@ -371,6 +371,12 @@ function createContext(options={}) {
         return;
       }
 
+      // via https://github.com/HubSpot/drop/pull/171
+      if (!this.drop) {
+        // The instance was destroyed
+        return;
+      }
+
       if (!this.drop.parentNode) {
         document.body.appendChild(this.drop);
       }