diff --git a/test/phpunit/ImagesLibTest.php b/test/phpunit/ImagesLibTest.php
index 5d956fcf3c7..4835a8afd76 100644
--- a/test/phpunit/ImagesLibTest.php
+++ b/test/phpunit/ImagesLibTest.php
@@ -163,9 +163,9 @@ class ImagesLibTest extends PHPUnit\Framework\TestCase
 		global $conf;
 
 		$file=dirname(__FILE__).'/img250x20.png';
-		$filetarget=$conf->admin->dir_temp.'/img250x20.webp';
+		$filetarget=$conf->admin->dir_temp.'/img250x20.jpg';
 		$result = dol_imageResizeOrCrop($file, 0, 0, 0, 0, 0, $filetarget);
 		print __METHOD__." result=".$result."\n";
-		$this->assertEquals($filetarget, $result, 'Failed to convert into webp');
+		$this->assertEquals($filetarget, $result, 'Failed to convert into '.$filetarget);
 	}
 }