diff --git a/src/components/ImageUploadDialog.vue b/src/components/ImageUploadDialog.vue
index 63425491..04a65e3d 100644
--- a/src/components/ImageUploadDialog.vue
+++ b/src/components/ImageUploadDialog.vue
@@ -67,7 +67,8 @@ async function downloadImage(url: string) {
   let extension = '';
 
   if (blob.type === 'image/jpeg') extension = '.jpg';
-  if (blob.type === 'image/png') extension = '.png';
+  else if (blob.type === 'image/png') extension = '.png';
+  else return;
 
   let a = document.createElement('a');
   a.download = `download${extension}`;