diff --git a/application/clicommands/MigrateCommand.php b/application/clicommands/MigrateCommand.php
index 6d034ee39..17892bb45 100644
--- a/application/clicommands/MigrateCommand.php
+++ b/application/clicommands/MigrateCommand.php
@@ -496,9 +496,8 @@ public function dashboardAction(): void
             );
 
             $changed = false;
-            /** @var ConfigObject $dashboardConfig */
+            /** @var ConfigObject<string> $dashboardConfig */
             foreach ($dashboardsConfig->getConfigObject() as $name => $dashboardConfig) {
-                /** @var ?string $dashboardUrlString */
                 $dashboardUrlString = $dashboardConfig->get('url');
                 if ($dashboardUrlString !== null) {
                     $dashBoardUrl = Url::fromPath($dashboardUrlString, [], new Request());
@@ -595,9 +594,8 @@ public function filterAction(): void
     private function transformNavigationItems(Config $config, string $owner, int &$rc): bool
     {
         $updated = false;
-        /** @var ConfigObject $newConfigObject */
+        /** @var ConfigObject<string> $newConfigObject */
         foreach ($config->getConfigObject() as $section => $newConfigObject) {
-            /** @var string $configOwner */
             $configOwner = $newConfigObject->get('owner') ?? '';
             if ($configOwner && $configOwner !== $owner) {
                 continue;
@@ -686,9 +684,8 @@ private function migrateNavigationItems(Config $config, string $owner, string $p
         $newConfig = $config->getConfigFile() === $path ? $config : $this->readFromIni($path, $rc);
 
         $updated = false;
-        /** @var ConfigObject $configObject */
+        /** @var ConfigObject<string> $configObject */
         foreach ($config->getConfigObject() as $configObject) {
-            /** @var string $configOwner */
             $configOwner = $configObject->get('owner') ?? '';
             if ($configOwner && $configOwner !== $owner) {
                 continue;
diff --git a/library/Icingadb/Command/Transport/CommandTransport.php b/library/Icingadb/Command/Transport/CommandTransport.php
index ea125bc81..952cb1486 100644
--- a/library/Icingadb/Command/Transport/CommandTransport.php
+++ b/library/Icingadb/Command/Transport/CommandTransport.php
@@ -50,7 +50,7 @@ public static function getConfig(): Config
     /**
      * Create a transport from config
      *
-     * @param   ConfigObject  $config
+     * @param   ConfigObject<string>  $config
      *
      * @return  ApiCommandTransport
      *
@@ -59,7 +59,7 @@ public static function getConfig(): Config
     public static function createTransport(ConfigObject $config): ApiCommandTransport
     {
         $config = clone $config;
-        switch (strtolower($config->transport)) {
+        switch (strtolower($config->transport ?? '')) {
             case ApiCommandTransport::TRANSPORT:
                 $transport = new ApiCommandTransport();
                 break;
diff --git a/library/Icingadb/Compat/CompatObject.php b/library/Icingadb/Compat/CompatObject.php
index 6a30751d3..1d9657db8 100644
--- a/library/Icingadb/Compat/CompatObject.php
+++ b/library/Icingadb/Compat/CompatObject.php
@@ -361,13 +361,14 @@ protected function getDataView()
      */
     private function getBoolType($value)
     {
-        switch ($value) {
-            case false:
-                return 0;
-            case true:
-                return 1;
-            case 'sticky':
-                return 2;
+        if ($value === 'sticky') {
+            return 2;
         }
+
+        if (is_string($value)) {
+            return null;
+        }
+
+        return (int) $value;
     }
 }
diff --git a/library/Icingadb/Widget/ItemTable/BaseHostGroupItem.php b/library/Icingadb/Widget/ItemTable/BaseHostGroupItem.php
index c56a1f8f6..b3099c802 100644
--- a/library/Icingadb/Widget/ItemTable/BaseHostGroupItem.php
+++ b/library/Icingadb/Widget/ItemTable/BaseHostGroupItem.php
@@ -5,7 +5,7 @@
 namespace Icinga\Module\Icingadb\Widget\ItemTable;
 
 use Icinga\Module\Icingadb\Common\Links;
-use Icinga\Module\Icingadb\Model\Hostgroup;
+use Icinga\Module\Icingadb\Model\Hostgroupsummary;
 use ipl\Html\Attributes;
 use ipl\Html\BaseHtmlElement;
 use ipl\Html\HtmlElement;
@@ -18,7 +18,7 @@
 /**
  * Hostgroup item of a hostgroup list. Represents one database row.
  *
- * @property Hostgroup $item
+ * @property Hostgroupsummary $item
  * @property HostgroupTable $table
  */
 abstract class BaseHostGroupItem extends BaseTableRowItem
diff --git a/library/Icingadb/Widget/ItemTable/BaseServiceGroupItem.php b/library/Icingadb/Widget/ItemTable/BaseServiceGroupItem.php
index 7bee532ef..24f0beaae 100644
--- a/library/Icingadb/Widget/ItemTable/BaseServiceGroupItem.php
+++ b/library/Icingadb/Widget/ItemTable/BaseServiceGroupItem.php
@@ -5,7 +5,7 @@
 namespace Icinga\Module\Icingadb\Widget\ItemTable;
 
 use Icinga\Module\Icingadb\Common\Links;
-use Icinga\Module\Icingadb\Model\Servicegroup;
+use Icinga\Module\Icingadb\Model\ServicegroupSummary;
 use ipl\Html\Attributes;
 use ipl\Html\BaseHtmlElement;
 use ipl\Html\HtmlElement;
@@ -18,7 +18,7 @@
 /**
  * Servicegroup item of a servicegroup list. Represents one database row.
  *
- * @property Servicegroup $item
+ * @property ServicegroupSummary $item
  * @property ServicegroupTable $table
  */
 abstract class BaseServiceGroupItem extends BaseTableRowItem
diff --git a/library/Icingadb/Widget/ItemTable/HostgroupTableRow.php b/library/Icingadb/Widget/ItemTable/HostgroupTableRow.php
index 6aa61c271..cb3f06a9a 100644
--- a/library/Icingadb/Widget/ItemTable/HostgroupTableRow.php
+++ b/library/Icingadb/Widget/ItemTable/HostgroupTableRow.php
@@ -4,7 +4,7 @@
 
 namespace Icinga\Module\Icingadb\Widget\ItemTable;
 
-use Icinga\Module\Icingadb\Model\Hostgroup;
+use Icinga\Module\Icingadb\Model\Hostgroupsummary;
 use Icinga\Module\Icingadb\Widget\Detail\HostStatistics;
 use Icinga\Module\Icingadb\Widget\Detail\ServiceStatistics;
 use ipl\Html\BaseHtmlElement;
@@ -13,7 +13,7 @@
 /**
  * Hostgroup table row of a hostgroup table. Represents one database row.
  *
- * @property Hostgroup $item
+ * @property Hostgroupsummary $item
  * @property HostgroupTable $table
  */
 class HostgroupTableRow extends BaseHostGroupItem
diff --git a/library/Icingadb/Widget/ItemTable/ServicegroupTableRow.php b/library/Icingadb/Widget/ItemTable/ServicegroupTableRow.php
index 3dea4c1e5..e34c029ff 100644
--- a/library/Icingadb/Widget/ItemTable/ServicegroupTableRow.php
+++ b/library/Icingadb/Widget/ItemTable/ServicegroupTableRow.php
@@ -4,7 +4,7 @@
 
 namespace Icinga\Module\Icingadb\Widget\ItemTable;
 
-use Icinga\Module\Icingadb\Model\Servicegroup;
+use Icinga\Module\Icingadb\Model\ServicegroupSummary;
 use Icinga\Module\Icingadb\Widget\Detail\ServiceStatistics;
 use ipl\Html\BaseHtmlElement;
 use ipl\Stdlib\Filter;
@@ -12,7 +12,7 @@
 /**
  * Servicegroup item of a servicegroup list. Represents one database row.
  *
- * @property Servicegroup $item
+ * @property ServicegroupSummary $item
  * @property ServicegroupTable $table
  */
 class ServicegroupTableRow extends BaseServiceGroupItem