fix #3086

Closes #3086

Merge request studip/studip!2069

resources/vue/components/courseware/CoursewareBlockEdit.vue

 <template>
     <section class="cw-block-edit">
-        <header>{{ $gettext('Bearbeiten') }}</header>
+        <header v-if="preview">{{ $gettext('Bearbeiten') }}</header>
         <div class="cw-block-features-content">
             <div @click="deactivateToolbar(); exitHandler = true;">
                 <slot name="edit" />
@@ -20,6 +20,7 @@ export default {
     name: 'courseware-block-edit',
     props: {
         block: Object,
+        preview: Boolean
     },
     data() {
         return {

resources/vue/components/courseware/CoursewareDefaultBlock.vue

@@ -39,6 +39,7 @@
                     <courseware-block-edit
                         v-if="canEdit && showEdit"
                         :block="block"
+                        :preview="preview"
                         @store="prepareStoreEdit"
                         @close="closeEdit"
                     >