Lazy load attachment images by default

src/components/attachment/attachment.vue

@@ -155,6 +155,7 @@
       >
         <StillImage
           class="image"
+          :loading="'lazy'"
           :referrerpolicy="referrerpolicy"
           :mimetype="attachment.mimetype"
           :src="attachment.large_thumb_url || attachment.url"

src/components/still-image/still-image.js

@@ -1,5 +1,6 @@
 const StillImage = {
   props: [
+    'loading',
     'src',
     'referrerpolicy',
     'mimetype',

src/components/still-image/still-image.vue

@@ -12,6 +12,7 @@
     <img
       ref="src"
       :key="src"
+      :loading="loading"
       :alt="alt"
       :title="alt"
       :src="src"