diff --git a/front/src/components/auth/LoginForm.vue b/front/src/components/auth/LoginForm.vue
index 03e9b4ecb..7abb98586 100644
--- a/front/src/components/auth/LoginForm.vue
+++ b/front/src/components/auth/LoginForm.vue
@@ -111,7 +111,7 @@ export default {
       },
       error: '',
       isLoading: false,
-      domain: document.domain
+      domain: location.hostname
     }
   },
   computed: {
@@ -134,7 +134,7 @@ export default {
   },
   methods: {
     async submit () {
-      if (document.domain === this.$store.getters['instance/domain']) {
+      if (location.hostname === this.$store.getters['instance/domain']) {
         return await this.submitSession()
       } else {
         this.isLoading = true
diff --git a/front/src/store/instance.ts b/front/src/store/instance.ts
index 579440dbd..fd1c5258d 100644
--- a/front/src/store/instance.ts
+++ b/front/src/store/instance.ts
@@ -139,14 +139,7 @@ const store: Module<State, RootState> = {
       const instanceUrl = state.instanceUrl ?? location.origin
       return instanceUrl + relativeUrl
     },
-    domain: (state) => {
-      if (!state.instanceUrl) return null
-
-      const url = state.instanceUrl
-      const parser = document.createElement('a')
-      parser.href = url
-      return parser.hostname
-    },
+    domain: (state) => new URL(state.instanceUrl ?? location.origin).hostname,
     appDomain: () => location.hostname
   },
   actions: {