Update

autoload/rubycomplete.vim

@@ -589,11 +589,13 @@ class VimRubyCompletion
 # {{{ main completion code
   def self.preload_rails
     a = VimRubyCompletion.new
-    require 'Thread'
-    Thread.new(a) do |b|
-      begin
-      b.load_rails
-      rescue
+    if VIM::evaluate("has('nvim')") == 0
+      require 'thread'
+      Thread.new(a) do |b|
+        begin
+        b.load_rails
+        rescue
+        end
       end
     end
     a.load_rails