diff --git a/data/web/js/build/013-mailcow.js b/data/web/js/build/013-mailcow.js
index 01baa547b..08c6060d2 100644
--- a/data/web/js/build/013-mailcow.js
+++ b/data/web/js/build/013-mailcow.js
@@ -613,6 +613,8 @@ $(document).ready(function() {
     $form.find('input[name="password1"]').prop('required', !isOauth);
     $form.find('.oauth-source-hint').toggle(isOauth);
     $form.find('.imapsync-oauth-connect-row').toggle(isAuthCode);
+    $form.find('.imapsync-user1-row').toggle(!isAuthCode);
+    $form.find('input[name="user1"]').prop('required', !isAuthCode);
   });
 
   // Source editor: OAuth block + authorization_code fields
diff --git a/data/web/templates/edit/syncjob.twig b/data/web/templates/edit/syncjob.twig
index b575f555b..2d171792c 100644
--- a/data/web/templates/edit/syncjob.twig
+++ b/data/web/templates/edit/syncjob.twig
@@ -24,7 +24,7 @@
         <small class="text-muted oauth-source-hint" style="display:{% if result.source_auth_type == 'XOAUTH2' %}block{% else %}none{% endif %};">{{ lang.syncjobs.oauth_source_hint }}</small>
       </div>
     </div>
-    <div class="row mb-2">
+    <div class="row mb-2 imapsync-user1-row" style="display:{% if result.source_oauth_flow == 'authorization_code' %}none{% else %}flex{% endif %};">
       <label class="control-label col-sm-2" for="user1">{{ lang.edit.username }}</label>
       <div class="col-sm-10">
         <input type="text" class="form-control" name="user1" id="user1" value="{{ result.user1 }}">
diff --git a/data/web/templates/modals/mailbox.twig b/data/web/templates/modals/mailbox.twig
index 46dce2353..2dda0b3a4 100644
--- a/data/web/templates/modals/mailbox.twig
+++ b/data/web/templates/modals/mailbox.twig
@@ -962,7 +962,7 @@
               <small class="text-muted oauth-source-hint" style="display:none;">{{ lang.syncjobs.oauth_source_hint }}</small>
             </div>
           </div>
-          <div class="row mb-2">
+          <div class="row mb-2 imapsync-user1-row">
             <label class="control-label col-sm-2 text-sm-end" for="user1">{{ lang.add.username }}</label>
             <div class="col-sm-10">
               <input type="text" class="form-control" name="user1" required>
diff --git a/data/web/templates/modals/user.twig b/data/web/templates/modals/user.twig
index 314f28f93..fda61d691 100644
--- a/data/web/templates/modals/user.twig
+++ b/data/web/templates/modals/user.twig
@@ -46,7 +46,7 @@
               <small class="text-muted oauth-source-hint" style="display:none;">{{ lang.syncjobs.oauth_source_hint }}</small>
             </div>
           </div>
-          <div class="row mb-2">
+          <div class="row mb-2 imapsync-user1-row">
             <label class="control-label col-sm-2" for="user1">{{ lang.add.username }}</label>
             <div class="col-sm-10">
               <input type="text" class="form-control" name="user1" required>