Ticket #54476: shim-for-testing.diff

src/wp-admin/includes/class-wp-debug-data.php

@@ -603 +603 @@
                                 $formats = array();
                         }
 
+                        $formats = array_diff( $formats, array( 'WEBP' ) );
+
                         $info['wp-media']['fields']['imagemagick_file_formats'] = array(
                                 'label' => __( 'ImageMagick supported file formats' ),
                                 'value' => ( empty( $formats ) ) ? __( 'Unable to determine' ) : implode( ', ', $formats ),

src/wp-includes/class-wp-image-editor-imagick.php

@@ -108 +108 @@
                                 return false;
                 }
 
+                // Disable support for WebP.
+                if ('image/webp' === $mime_type ) {
+                        return false;
+                }
+
                 try {
                         // phpcs:ignore WordPress.PHP.NoSilencedErrors.Discouraged
                         return ( (bool) @Imagick::queryFormats( $imagick_extension ) );