diff --git a/public/app/app.js b/public/app/app.js
index 2616c66e9f19e6432855c6737d2981feea97a24a..dc73839a26e022e6897a689da097073f55b71a43 100644
--- a/public/app/app.js
+++ b/public/app/app.js
@@ -3,16 +3,16 @@ var vm = new Vue({
   data: {
     files: {
       up: null,
-      dirs: null,
-      files: null,
+      dirs: [],
+      files: [],
       existing_describo: false
     },
     context: {
-      entities: null,
+      entities: [],
       root: null
     },
     schema: {
-      types: null,
+      types: [],
       properties: null
     },
     prop: {"name": "nom", "value": "val"},
diff --git a/public/app/components.js b/public/app/components.js
index 28a429c13b8dc56f8323ca53f0d776079fd82c58..a0f4994a79c707f9ee81546c7f544d9c78f898d8 100644
--- a/public/app/components.js
+++ b/public/app/components.js
@@ -35,6 +35,7 @@ var components = function () {
               v-bind:schema="schema"
               v-bind:val="values[i_index + page * 20]"
               v-bind:i_index="i_index"
+              :key="i_index"
               >
           </show-value>
         </details>
@@ -60,7 +61,9 @@ var components = function () {
             v-bind:values="values"
             v-bind:schema="schema"
             v-bind:val="val"
-            v-bind:i_index="i_index">
+            v-bind:i_index="i_index"
+            :key="i_index"
+           >
           </show-value>
        </template>
       </div>
diff --git a/views/index.ejs b/views/index.ejs
index 3f4f8baddf345457a79b50818965ce4adc5acbb1..5e2ca3da5f74771895c3c53e347fd8b5a75866ca 100644
--- a/views/index.ejs
+++ b/views/index.ejs
@@ -25,7 +25,7 @@
     <div class="collapse navbar-collapse" id="navbarSupportedContent">
       <div class="navbar-nav">
         <div class="navbar-item mr-auto">
-          <a v-if="dataset_path" class="nav-link"
+          <a v-if="dataset_path && display_path" class="nav-link"
              v-bind:href="'/?path=' + display_path + '&dataset_path=' +  display_path">
             <template v-if="files && files.existing_describo">
               Edit existing data package
@@ -46,7 +46,7 @@
         </div>
         <div v-if="dataset_path" class="navbar-item mr-auto">
           <a class="nav-link"
-             v-if="dataset_path && files && files.existing_catalog"
+             v-if="dataset_path && display_path && files && files.existing_catalog"
              v-bind:href="'/import_crate?path=' + display_path + '&dataset_path=' +  display_path">
             <span
               v-if="files.existing_describo"
@@ -77,7 +77,7 @@
               </div>
             </div>
           </div>
-          <div class="navbar-item mr-auto ">
+          <div class="navbar-item mr-auto">
             <form class="form-inline" v-on:submit.prevent="addContext()">
               <select class="custom-select" v-model="type">
                 <option
@@ -85,8 +85,6 @@
                   v-for="type_name in Object.getOwnPropertyNames(schema.types).filter(type => {return schema.types[type].create})"
                   v-bind:value="type_name"> {{ type_name }}
                 </option>
-                <option></option>
-              </select>
               </select>
               <button class="btn btn-secondary" type="submit">Add contextual item</button>
             </form>