diff --git a/addon/components/category-nav/category.js b/addon/components/category-nav/category.js
index 755d78d8..2a167440 100644
--- a/addon/components/category-nav/category.js
+++ b/addon/components/category-nav/category.js
@@ -91,7 +91,10 @@ export default class CategoryNavCategoryComponent extends Component {
     this.dragCounter = 0;
     this.isDragOver = false;
 
-    if (event.dataTransfer.files.length) {
+    if (
+      event.dataTransfer.files.length &&
+      !event.dataTransfer.getData("text")
+    ) {
       return await this.documents.upload(
         this.args.category,
         event.dataTransfer.files,
@@ -104,7 +107,7 @@ export default class CategoryNavCategoryComponent extends Component {
       documentIds.map(async (id) => {
         const document = this.store.peekRecord("document", id);
 
-        if (document.category.id === this.args.category.id) {
+        if (!document || document.category.id === this.args.category.id) {
           return true;
         }
 
diff --git a/addon/components/document-list-item.hbs b/addon/components/document-list-item.hbs
index 04d1adff..c1d21281 100644
--- a/addon/components/document-list-item.hbs
+++ b/addon/components/document-list-item.hbs
@@ -26,6 +26,7 @@
         <div
           class="document-thumbnail"
           uk-dropdown="pos: right-center; offset: 15; delay-show: 400; delay-hide: 100; container: .alexandria-container;"
+          {{on "dragstart" (fn (optional @onDragStart) @document)}}
         >
           <img
             data-src="{{@document.thumbnail.value}}"
diff --git a/tests/integration/components/category-nav/category-test.js b/tests/integration/components/category-nav/category-test.js
index 9780fbec..a9a1f064 100644
--- a/tests/integration/components/category-nav/category-test.js
+++ b/tests/integration/components/category-nav/category-test.js
@@ -55,7 +55,8 @@ module("Integration | Component | category-nav/category", function (hooks) {
     await triggerEvent("[data-test-drop]", "drop", {
       dataTransfer: {
         getData: () => documents.map((d) => d.id).join(","),
-        files: [],
+        // sometimes browser send a file as well (e.g. when dragging a thumbnail) - this should be ignored
+        files: [new File(["Thumbnail"], "test-file.txt")],
       },
     });
 
@@ -91,7 +92,7 @@ module("Integration | Component | category-nav/category", function (hooks) {
 
     await triggerEvent("[data-test-drop]", "drop", {
       dataTransfer: {
-        getData: () => {},
+        getData: () => "",
         files: [new File(["Ember Rules!"], "test-file.txt")],
       },
     });