diff --git a/wp-content/themes/ccat/app/components/site/SiteHeaderTopAuth.vue b/wp-content/themes/ccat/app/components/site/SiteHeaderTopAuth.vue
index b6af890..94f7847 100644
--- a/wp-content/themes/ccat/app/components/site/SiteHeaderTopAuth.vue
+++ b/wp-content/themes/ccat/app/components/site/SiteHeaderTopAuth.vue
@@ -1,7 +1,7 @@
 <script setup lang="ts">
 const props = defineProps<{ showLabels: boolean }>();
 const { loggedIn } = useUserSession();
-const label = computed(() => props.showLabels ? (loggedIn ? "Déconnexion" : "Connexion") : undefined);
+const label = computed(() => props.showLabels ? (loggedIn.value ? "Déconnexion" : "Connexion") : undefined);
 </script>
 
 <template>
diff --git a/wp-content/themes/ccat/app/composables/useNodeByUri.ts b/wp-content/themes/ccat/app/composables/useNodeByUri.ts
index c21910a..70cb958 100644
--- a/wp-content/themes/ccat/app/composables/useNodeByUri.ts
+++ b/wp-content/themes/ccat/app/composables/useNodeByUri.ts
@@ -3,8 +3,8 @@ import { ThePage, TheArticle, TheEvent, TheLocation, TheMembership, TheProject,
 
 export async function useNodeByUri(uri: string) {
   const { data, error } = await useAsyncGraphqlQuery("nodeByUri", { uri }, { graphqlCaching: { client: true } });
-  if (error.value) {
-    throw createError({ statusCode: 500, statusMessage: "Erreur serveur", message: error.value.message });
+  if (error.value || data.value?.errors.length) {
+    throw createError({ statusCode: 500, statusMessage: "Erreur serveur", message: "Une erreur est survenue." });
   }
   const node = data.value?.data.nodeByUri;
   const breadcrumbs = node?.breadcrumbs?.map(({ label, to }) => ({ label, to: to || undefined })) || [];
diff --git a/wp-content/themes/ccat/app/composables/useUserSwitching.ts b/wp-content/themes/ccat/app/composables/useUserSwitching.ts
index 739e8b1..ab2164c 100644
--- a/wp-content/themes/ccat/app/composables/useUserSwitching.ts
+++ b/wp-content/themes/ccat/app/composables/useUserSwitching.ts
@@ -3,7 +3,7 @@ export function useUserSwitching() {
   const { fetch: refreshUserSession } = useUserSession();
   const { session } = useUserSession();
 
-  const isUserSwitched = computed(() => Boolean(session.value?.switchedBy));
+  const isUserSwitched = computed(() => Boolean(session.value?.isSwitchedTo));
 
   async function userSwitchTo(userId: string | number) {
     try {
diff --git a/wp-content/themes/ccat/package.json b/wp-content/themes/ccat/package.json
index 43886bc..2bb76a1 100644
--- a/wp-content/themes/ccat/package.json
+++ b/wp-content/themes/ccat/package.json
@@ -25,6 +25,7 @@
     "@nuxtjs/robots": "5.5.0",
     "@nuxtjs/sitemap": "7.4.3",
     "@vueuse/nuxt": "13.7.0",
+    "es-toolkit": "^1.39.10",
     "nuxt": "^4.1.2",
     "nuxt-auth-utils": "0.5.23",
     "nuxt-graphql-middleware": "5.2.0",
diff --git a/wp-content/themes/ccat/pnpm-lock.yaml b/wp-content/themes/ccat/pnpm-lock.yaml
index 8502540..fb212bd 100644
--- a/wp-content/themes/ccat/pnpm-lock.yaml
+++ b/wp-content/themes/ccat/pnpm-lock.yaml
@@ -35,6 +35,9 @@ importers:
       '@vueuse/nuxt':
         specifier: 13.7.0
         version: 13.7.0(magicast@0.3.5)(nuxt@4.1.2(@netlify/blobs@9.1.2)(@parcel/watcher@2.5.1)(@types/node@24.4.0)(@vue/compiler-sfc@3.5.21)(db0@0.3.2)(eslint@9.35.0(jiti@2.5.1))(ioredis@5.7.0)(lightningcss@1.30.1)(magicast@0.3.5)(optionator@0.9.4)(rollup@4.50.2)(terser@5.44.0)(typescript@5.9.2)(vite@7.1.5(@types/node@24.4.0)(jiti@2.5.1)(lightningcss@1.30.1)(terser@5.44.0)(yaml@2.8.1))(vue-tsc@3.0.7(typescript@5.9.2))(yaml@2.8.1))(vue@3.5.21(typescript@5.9.2))
+      es-toolkit:
+        specifier: ^1.39.10
+        version: 1.39.10
       nuxt:
         specifier: ^4.1.2
         version: 4.1.2(@netlify/blobs@9.1.2)(@parcel/watcher@2.5.1)(@types/node@24.4.0)(@vue/compiler-sfc@3.5.21)(db0@0.3.2)(eslint@9.35.0(jiti@2.5.1))(ioredis@5.7.0)(lightningcss@1.30.1)(magicast@0.3.5)(optionator@0.9.4)(rollup@4.50.2)(terser@5.44.0)(typescript@5.9.2)(vite@7.1.5(@types/node@24.4.0)(jiti@2.5.1)(lightningcss@1.30.1)(terser@5.44.0)(yaml@2.8.1))(vue-tsc@3.0.7(typescript@5.9.2))(yaml@2.8.1)
@@ -3305,6 +3308,9 @@ packages:
     resolution: {integrity: sha512-FGgH2h8zKNim9ljj7dankFPcICIK9Cp5bm+c2gQSYePhpaG5+esrLODihIorn+Pe6FGJzWhXQotPv73jTaldXA==}
     engines: {node: '>= 0.4'}
 
+  es-toolkit@1.39.10:
+    resolution: {integrity: sha512-E0iGnTtbDhkeczB0T+mxmoVlT4YNweEKBLq7oaU4p11mecdsZpNWOglI4895Vh4usbQ+LsJiuLuI2L0Vdmfm2w==}
+
   esbuild@0.25.4:
     resolution: {integrity: sha512-8pgjLUcUjcgDg+2Q4NYXnPbo/vncAY4UmyaCm0jZevERqCHZIaWwdJHkf8XQtu4AxSKCdvrUbT0XUr1IdZzI8Q==}
     engines: {node: '>=18'}
@@ -9767,6 +9773,8 @@ snapshots:
       es-errors: 1.3.0
     optional: true
 
+  es-toolkit@1.39.10: {}
+
   esbuild@0.25.4:
     optionalDependencies:
       '@esbuild/aix-ppc64': 0.25.4
diff --git a/wp-content/themes/ccat/server/api/switch-back.post.ts b/wp-content/themes/ccat/server/api/switch-back.post.ts
index e88e221..ff017f4 100644
--- a/wp-content/themes/ccat/server/api/switch-back.post.ts
+++ b/wp-content/themes/ccat/server/api/switch-back.post.ts
@@ -2,8 +2,7 @@ import { defineEventHandler } from "h3";
 
 export default defineEventHandler(async (event) => {
   try {
-    // TODO: Switch back to the previous user.
-    await clearUserSession(event);
+    await handleSwitchBack(event);
     return { success: true };
   }
   catch (error) {
diff --git a/wp-content/themes/ccat/server/graphqlMiddleware.serverOptions.ts b/wp-content/themes/ccat/server/graphqlMiddleware.serverOptions.ts
index c753f4d..c24893b 100644
--- a/wp-content/themes/ccat/server/graphqlMiddleware.serverOptions.ts
+++ b/wp-content/themes/ccat/server/graphqlMiddleware.serverOptions.ts
@@ -32,44 +32,15 @@ export default defineGraphqlServerOptions({
     return { headers: { ...headers, Authorization: `Bearer ${session.secure.authToken}` } };
   },
 
-  onServerResponse(event, response, _operation, operationName) {
-    // Handle login mutation
-    if (operationName === "login") {
-      const loginData = response._data as LoginRootMutation;
-      if (loginData?.login) {
-        const { authToken, refreshToken, user } = loginData.login;
-        setUserSession(event, {
-          user: {
-            id: user?.id,
-            email: user?.email,
-          },
-          secure: {
-            authToken,
-            refreshToken,
-          },
-        });
-      }
+  async onServerResponse(event, response, _operation, operationName) {
+    switch (operationName) {
+      case "login":
+        await handleLogin(event, response._data!.data as LoginRootMutation);
+        break;
+      case "userSwitchTo":
+        await handleSwitchTo(event, response._data!.data as UserSwitchToRootMutation);
+        break;
     }
-
-    // Handle user switch mutations
-    if (operationName === "userSwitchTo") {
-      const switchData = response._data as UserSwitchToRootMutation;
-      if (switchData?.userSwitchTo?.authToken) {
-        const { authToken, refreshToken, user } = switchData.userSwitchTo;
-        setUserSession(event, {
-          user: {
-            id: user?.id,
-            email: user?.email,
-          },
-          secure: {
-            authToken,
-            refreshToken,
-          },
-        });
-      }
-    }
-
-    // Return the original response data
     return response._data!;
   },
 });
diff --git a/wp-content/themes/ccat/server/utils/auth.ts b/wp-content/themes/ccat/server/utils/auth.ts
new file mode 100644
index 0000000..9e950e5
--- /dev/null
+++ b/wp-content/themes/ccat/server/utils/auth.ts
@@ -0,0 +1,65 @@
+import type { LoginRootMutation, UserSwitchToRootMutation } from "#graphql-operations";
+import type { H3Event } from "h3";
+import { pick } from "es-toolkit/compat";
+
+export async function handleLogin(event: H3Event, loginData?: LoginRootMutation) {
+  if (!loginData?.login?.user) {
+    return;
+  }
+  const { authToken, refreshToken, user } = loginData.login;
+  await setUserSession(event, {
+    user: {
+      id: user.id,
+      email: user.email,
+    },
+    secure: {
+      authToken,
+      refreshToken,
+    },
+    loggedInAt: new Date().toISOString(),
+    isSwitchedTo: false,
+  });
+}
+
+export async function handleLogout(event: H3Event) {
+  await clearUserSession(event);
+}
+
+export async function handleSwitchTo(event: H3Event, data?: UserSwitchToRootMutation) {
+  if (!data?.userSwitchTo?.user) {
+    return;
+  }
+  const session = await getUserSession(event);
+  const { authToken, refreshToken, user } = data.userSwitchTo;
+  await setUserSession(event, {
+    user: {
+      id: user.id,
+      email: user.email,
+    },
+    secure: {
+      authToken,
+      refreshToken,
+      previous: {
+        user: session.user,
+        loggedInAt: session.loggedInAt,
+        secure: pick(session.secure, ["authToken", "refreshToken"]),
+      },
+    },
+    loggedInAt: new Date().toISOString(),
+    isSwitchedTo: true,
+  });
+}
+
+export async function handleSwitchBack(event: H3Event) {
+  const session = await getUserSession(event);
+  if (!session.secure?.previous) {
+    return;
+  }
+  const { user, loggedInAt, secure } = session.secure.previous;
+  await setUserSession(event, {
+    user,
+    secure,
+    loggedInAt,
+    isSwitchedTo: false,
+  });
+}
diff --git a/wp-content/themes/ccat/shared/types/auth.d.ts b/wp-content/themes/ccat/shared/types/auth.d.ts
index 852711f..7fadddd 100644
--- a/wp-content/themes/ccat/shared/types/auth.d.ts
+++ b/wp-content/themes/ccat/shared/types/auth.d.ts
@@ -7,12 +7,17 @@ declare module "#auth-utils" {
 
   interface UserSession {
     loggedInAt: string;
-    switchedBy?: number;
+    isSwitchedTo: boolean;
   }
 
   interface SecureSessionData {
     authToken: string;
     refreshToken: string;
+    previous?: {
+      user: User;
+      loggedInAt: string;
+      secure: Pick<SecureSessionData, ["authToken", "refreshToken"]>;
+    };
   }
 }