Fix poststatusform attachment markup.

src/components/attachment/attachment.vue

@@ -42,6 +42,15 @@
               width: 100%;
           }
 
+          img.media-upload {
+              width: 100%;
+              height: 100%;
+              flex: 1;
+              border: 1px solid;
+              border-radius: 0.5em;
+          }
+
+
           .oembed {
               img {
                   width: 100%;