diff --git a/Neos.Neos/Classes/Command/UserCommandController.php b/Neos.Neos/Classes/Command/UserCommandController.php
index f0e1f20808c..9b705f291c9 100644
--- a/Neos.Neos/Classes/Command/UserCommandController.php
+++ b/Neos.Neos/Classes/Command/UserCommandController.php
@@ -385,7 +385,7 @@ protected function getTableRowForUser(User $user)
         $accountIdentifiers = [];
         foreach ($user->getAccounts() as $account) {
             /** @var Account $account */
-            $authenticationProviderName = $account->getAuthenticationProviderName();
+            $authenticationProviderName = (string) $account->getAuthenticationProviderName();
             if ($authenticationProviderName !== $this->userService->getDefaultAuthenticationProviderName()) {
                 $authenticationProviderLabel = ' (' . (isset($this->authenticationProviderSettings[$authenticationProviderName]['label']) ? $this->authenticationProviderSettings[$authenticationProviderName]['label'] : $authenticationProviderName) . ')';
             } else {
diff --git a/Neos.Neos/Classes/Controller/Module/Administration/UsersController.php b/Neos.Neos/Classes/Controller/Module/Administration/UsersController.php
index d6ee0dd1392..3b7da720015 100644
--- a/Neos.Neos/Classes/Controller/Module/Administration/UsersController.php
+++ b/Neos.Neos/Classes/Controller/Module/Administration/UsersController.php
@@ -222,7 +222,7 @@ public function editAccountAction(Account $account): void
     {
         $this->view->assignMultiple([
             'account' => $account,
-            'user' => $this->userService->getUser($account->getAccountIdentifier(), $account->getAuthenticationProviderName()),
+            'user' => $this->userService->getUser($account->getAccountIdentifier(), (string) $account->getAuthenticationProviderName()),
             'availableRoles' => $this->policyService->getRoles()
         ]);
     }
@@ -242,7 +242,7 @@ public function editAccountAction(Account $account): void
      */
     public function updateAccountAction(Account $account, array $roleIdentifiers, array $password = []): void
     {
-        $user = $this->userService->getUser($account->getAccountIdentifier(), $account->getAuthenticationProviderName());
+        $user = $this->userService->getUser($account->getAccountIdentifier(), (string) $account->getAuthenticationProviderName());
         if ($user === $this->currentUser) {
             $roles = [];
             foreach ($roleIdentifiers as $roleIdentifier) {
diff --git a/Neos.Neos/Classes/Controller/Module/User/UserSettingsController.php b/Neos.Neos/Classes/Controller/Module/User/UserSettingsController.php
index 6333f74135f..cd45f309a61 100644
--- a/Neos.Neos/Classes/Controller/Module/User/UserSettingsController.php
+++ b/Neos.Neos/Classes/Controller/Module/User/UserSettingsController.php
@@ -115,7 +115,7 @@ public function editAccountAction(Account $account)
     {
         $this->view->assignMultiple([
             'account' => $account,
-            'user' => $this->userService->getUser($account->getAccountIdentifier(), $account->getAuthenticationProviderName())
+            'user' => $this->userService->getUser($account->getAccountIdentifier(), (string) $account->getAuthenticationProviderName())
         ]);
     }
 
diff --git a/Neos.Neos/Classes/Domain/Service/UserService.php b/Neos.Neos/Classes/Domain/Service/UserService.php
index bdb0bc20744..72b0f804116 100644
--- a/Neos.Neos/Classes/Domain/Service/UserService.php
+++ b/Neos.Neos/Classes/Domain/Service/UserService.php
@@ -221,7 +221,7 @@ public function getUsername(User $user, $authenticationProviderName = null)
         $authenticationProviderName = $authenticationProviderName ?: $this->defaultAuthenticationProviderName;
         foreach ($user->getAccounts() as $account) {
             /** @var Account $account */
-            if ($account->getAuthenticationProviderName() === $authenticationProviderName) {
+            if ((string) $account->getAuthenticationProviderName() === $authenticationProviderName) {
                 return $account->getAccountIdentifier();
             }
         }
@@ -375,7 +375,7 @@ public function setUserPassword(User $user, $password)
 
         foreach ($user->getAccounts() as $account) {
             /** @var Account $account */
-            $authenticationProviderName = $account->getAuthenticationProviderName();
+            $authenticationProviderName = (string) $account->getAuthenticationProviderName();
             if (isset($indexedTokens[$authenticationProviderName]) && $indexedTokens[$authenticationProviderName] instanceof UsernamePassword) {
                 $account->setCredentialsSource($this->hashService->hashPassword($password));
                 $this->accountRepository->update($account);
@@ -463,15 +463,16 @@ public function setRolesForAccount(Account $account, array $newRoleIdentifiers)
     {
         $currentRoles = $account->getRoles();
 
-        foreach ($currentRoles as $roleIdentifier => $role) {
-            $roleIdentifier = $this->normalizeRoleIdentifier($roleIdentifier);
+        /** @var Role $role */
+        foreach ($currentRoles as $role) {
+            $roleIdentifier = $this->normalizeRoleIdentifier((string) $role);
             if (!in_array($roleIdentifier, $newRoleIdentifiers)) {
                 $this->removeRoleFromAccount($account, $roleIdentifier);
             }
         }
 
         foreach ($newRoleIdentifiers as $roleIdentifier) {
-            if (!in_array($roleIdentifier, array_keys($currentRoles))) {
+            if (!$currentRoles->has(new Role($roleIdentifier))) {
                 $this->addRoleToAccount($account, $roleIdentifier);
             }
         }
@@ -490,7 +491,6 @@ public function addRoleToAccount(Account $account, $roleIdentifier)
     {
         $roleIdentifier = $this->normalizeRoleIdentifier($roleIdentifier);
         $role = $this->policyService->getRole($roleIdentifier);
-
         if (!$account->hasRole($role)) {
             $account->addRole($role);
             $this->accountRepository->update($account);
diff --git a/Neos.Neos/Classes/ViewHelpers/Backend/AuthenticationProviderLabelViewHelper.php b/Neos.Neos/Classes/ViewHelpers/Backend/AuthenticationProviderLabelViewHelper.php
index e14b3b4b07f..7c32eb3debb 100644
--- a/Neos.Neos/Classes/ViewHelpers/Backend/AuthenticationProviderLabelViewHelper.php
+++ b/Neos.Neos/Classes/ViewHelpers/Backend/AuthenticationProviderLabelViewHelper.php
@@ -43,7 +43,8 @@ public function initializeArguments()
      */
     public function render(): string
     {
-        $identifier = $this->arguments['identifier'];
+        $identifier = (string) $this->arguments['identifier'];
+
         return ($this->authenticationProviderSettings[$identifier]['label'] ?? $identifier);
     }
 }