fix

Author: Rom1-B

inc/field.class.php

@@ -1349,7 +1349,7 @@ public static function prepareHtmlFields(
                 $value = is_array($decoded) ? $decoded : [];
             }
 
-            if ($field['multiple'] && is_array($value)) {
+            if ($field['multiple']) {
                 // Flatten any nested arrays caused by corrupted DB data (double-encoded values)
                 // so that Dropdown::show() always receives a flat list of scalars.
                 $value = array_values(array_filter(

tests/Units/MassiveActionGlpiItemDropdownTest.php

@@ -64,7 +64,7 @@ public function setUp(): void
 
     public function tearDown(): void
     {
-        unset($_REQUEST['massiveaction'], $_POST);
+        unset($_REQUEST['massiveaction']);
         $this->tearDownFieldTest();
         GLPITestCase::tearDown();
     }

tests/Units/MassiveActionRealFlowTest.php

@@ -62,7 +62,7 @@ public function setUp(): void
 
     public function tearDown(): void
     {
-        unset($_REQUEST['massiveaction'], $_POST);
+        unset($_REQUEST['massiveaction']);
         $this->tearDownFieldTest();
         GLPITestCase::tearDown();
     }