Fix syntax errors and hiding logic.

This has been tested.

src/components/attachment/attachment.js

@@ -7,17 +7,19 @@ const Attachment = {
     'nsfw',
     'statusId'
   ],
-  data: () => ({
+  data () {
+    return {
       nsfwImage,
       hideNsfwLocal: this.$store.state.config.hideNsfw,
-    showHidden: !this.hideNsfwLocal
-  }),
+      showHidden: false
+    }
+  },
   computed: {
     type () {
       return fileTypeService.fileType(this.attachment.mimetype)
     },
     hidden () {
-      return this.nsfw && !this.showHidden
+      return this.nsfw && this.hideNsfwLocal && !this.showHidden
     }
   },
   methods: {

src/components/attachment/attachment.vue

@@ -1,9 +1,9 @@
 <template>
   <div class="attachment" :class="type">
-    <a class="image-attachment" v-if="hidden && hideNsfwLocal" v-on:click.prevent="toggleHidden()">
+    <a class="image-attachment" v-if="hidden" v-on:click.prevent="toggleHidden()">
       <img :key="nsfwImage" :src="nsfwImage"></img>
     </a>
-    <div class="hider" v-if="nsfw && !hidden && hideNsfwLocal">
+    <div class="hider" v-if="nsfw && hideNsfwLocal && !hidden">
       <a href="#" @click.prevent="toggleHidden()">Hide</a>
     </div>
 

src/components/settings/settings.js

@@ -3,7 +3,7 @@ import StyleSwitcher from '../style_switcher/style_switcher.vue'
 const settings = {
   data () {
     return {
-      hideAttachmentsLocal: this.$store.state.config.hideAttachments
+      hideAttachmentsLocal: this.$store.state.config.hideAttachments,
       hideNsfwLocal: this.$store.state.config.hideNsfw
     }
   },
@@ -13,7 +13,7 @@ const settings = {
   watch: {
     hideAttachmentsLocal (value) {
       this.$store.dispatch('setOption', { name: 'hideAttachments', value })
-    }
+    },
     hideNsfwLocal (value) {
       this.$store.dispatch('setOption', { name: 'hideNsfw', value })
     }