Updated zendesk_api gem because of "You are setting a key that conflicts with a built-in method Hashie::Mash#class defined in Kernel" warnings.

Gemfile.lock

@@ -60,7 +60,7 @@ GEM
     childprocess (0.5.9)
       ffi (~> 1.0, >= 1.0.11)
     clavius (1.0.2)
-    clearbit (0.2.5)
+    clearbit (0.2.7)
       nestful (~> 1.1.0)
     coderay (1.1.1)
     coffee-rails (4.2.1)
@@ -155,7 +155,7 @@ GEM
       guard
       guard-compat (~> 1.1)
     hashdiff (0.3.2)
-    hashie (3.5.5)
+    hashie (3.5.6)
     htmlentities (4.3.4)
     http (1.0.4)
       addressable (~> 2.3)
@@ -341,7 +341,6 @@ GEM
     sawyer (0.7.0)
       addressable (>= 2.3.5, < 2.5)
       faraday (~> 0.8, < 0.10)
-    scrub_rb (1.0.1)
     selenium-webdriver (2.53.4)
       childprocess (~> 0.5)
       rubyzip (~> 1.0)
@@ -413,13 +412,12 @@ GEM
       hashdiff
     websocket (1.2.3)
     writeexcel (1.0.5)
-    zendesk_api (1.14.0)
+    zendesk_api (1.14.4)
       faraday (~> 0.9)
-      hashie (>= 1.2, < 4.0, != 3.3.0)
+      hashie (>= 3.5.2, < 4.0.0)
       inflection
       mime-types
       multipart-post (~> 2.0)
-      scrub_rb (~> 1.0.1)
 
 PLATFORMS
   ruby

app/assets/javascripts/app/controllers/import_zendesk.coffee

@@ -116,7 +116,8 @@ class Index extends App.ControllerContent
   showCredentials: (e) =>
     e.preventDefault()
     @urlStatus.attr('data-state', '')
-    @zendeskUrlApiToken.attr('href', @zendeskUrl.val() + 'agent/admin/api')
+    url = @zendeskUrl.val() + '/agent/admin/api'
+    @zendeskUrlApiToken.attr('href', url.replace('//', '/'))
     @zendeskUrlApiToken.val('HERE')
     @$('[data-slide=zendesk-url]').toggleClass('hide')
     @$('[data-slide=zendesk-credentials]').toggleClass('hide')

app/controllers/import_zendesk_controller.rb

@@ -49,7 +49,9 @@ class ImportZendeskController < ApplicationController
       return
     end
 
-    Setting.set('import_zendesk_endpoint', "#{params[:url]}api/v2")
+    endpoint = "#{params[:url]}/api/v2"
+    endpoint.gsub('//', '/')
+    Setting.set('import_zendesk_endpoint', endpoint)
 
     render json: {
       result: 'ok',