diff --git a/lib/IdentSwitchForm.php b/lib/IdentSwitchForm.php
index 937a1cb..5369dc2 100644
--- a/lib/IdentSwitchForm.php
+++ b/lib/IdentSwitchForm.php
@@ -54,7 +54,7 @@ class IdentSwitchForm
 			$prefix . 'tls' => ['type' => 'checkbox'],
 			$prefix . 'username' => ['type' => 'text', 'size' => 64, 'placeholder' => $record['email'] ?? ''],
 			$prefix . 'password' => ['type' => 'password', 'size' => 64],
-			$prefix . 'delimiter' => ['type' => 'text', 'size' => 1, 'placeholder' => '.'],
+			$prefix . 'delimiter' => ['type' => 'text', 'size' => 1, 'placeholder' => 'Auto'],
 		];
 	}
 
diff --git a/lib/IdentSwitchSwitcher.php b/lib/IdentSwitchSwitcher.php
index 703c987..a18aeac 100644
--- a/lib/IdentSwitchSwitcher.php
+++ b/lib/IdentSwitchSwitcher.php
@@ -50,7 +50,7 @@ class IdentSwitchSwitcher
 				}
 			}
 
-			$_SESSION['imap_delimiter'] = $_SESSION['imap_delimiter' . ident_switch::MY_POSTFIX] ?? '.';
+			$_SESSION['imap_delimiter'] = $_SESSION['imap_delimiter' . ident_switch::MY_POSTFIX] ?? null;
 			$_SESSION['username'] = $rc->user->data['username'];
 			$_SESSION['password'] = $_SESSION['password' . ident_switch::MY_POSTFIX];
 			$_SESSION['iid' . ident_switch::MY_POSTFIX] = -1;
@@ -107,7 +107,7 @@ class IdentSwitchSwitcher
 					$host = "{$ssl}://" . $host;
 				}
 
-				$delimiter = $r['imap_delimiter'] ?: '.';
+				$delimiter = $r['imap_delimiter'] ?: null;
 
 				$_SESSION['storage_host'] = $host;
 				$_SESSION['storage_ssl'] = $ssl;