Attributes are not rendered when showing the source code
(I apologize if this has been already reported; I looked at the last issues and did not find one.)
Looking at GDToolkit.php, for example, I noticed the attributes are not shown in the code.
I was trying to understand how to convert the code for a module I maintain, and noticed there was the use Drupal\Core\ImageToolkit\Attribute\ImageToolkit; line which made me look at the code directly in the repository, where I noticed the code is the following one.
/**
* Defines the GD2 toolkit for image manipulation within Drupal.
*/
#[ImageToolkit(
id: "gd",
title: new TranslatableMarkup("GD2 image manipulation toolkit"),
)]
class GDToolkit extends ImageToolkitBase {