Only disable ldflex switch, don't hide.

src/views/Config.vue

@@ -7,8 +7,8 @@
   <br><br><br>
   <b-field horizontal style="display: flex;">
     <LoginButton />
-    <b-field v-if="! loggedIn" style="text-align: left;" message='Use <a target="blank" href="https://github.com/solid/query-ldflex">ldflex</a>'  title="This option makes troubles with older browsers and exotic network configuration. It can be savely disabled.">
-      <b-switch v-model="$store.state.ldflex"/>
+    <b-field style="text-align: left;" message='Use <a target="blank" href="https://github.com/solid/query-ldflex">ldflex</a>'  title="This option makes troubles with older browsers and exotic network configuration. It can be savely disabled.">
+      <b-switch :disabled="loggedIn" v-model="$store.state.ldflex" />
     </b-field>
   </b-field>
   <div v-if="loggedIn && $store.state.webId">