import merge, remove Core

public/js/wn/ui/appframe.js

@@ -50,6 +50,7 @@ wn.ui.AppFrame = Class.extend({
 	},
 	
 	add_module_tab: function(module) {
+		if(!erpnext.modules[module]) return;
 		this.add_tab('<span class="small-module-icons small-module-icons-'+
 			module.toLowerCase()+'"></span>'+' <span>'
 			+ wn._(module) + "</span>", 0.7, function() {

webnotes/modules/import_merge.py

@@ -76,6 +76,7 @@ class UpdateDocument:
 	def __init__(self, in_doclist=[]):
 		self.in_doclist = in_doclist
 		self.doc = Document(fielddata = in_doclist[0])
+		self.old_doc = None
 		self.modified = self.doc.modified # make a copy
 		self.doclist = []