[6.x]: Element behaviors not registering

[janhenckens]

What happened?

Description

Following the upgrade path outlined here, I required the yii2-adapter in my plugin and I'm testing if that covers everything.

My plugin registers a behavior or Entry/Categories/Products but those events aren't being picked up right now:

use craft\elements\Entry;
use craft\events\DefineBehaviorsEvent;
use studioespresso\seofields\behaviors\ElementSeoBehavior;

Event::on(Entry::class, Entry::EVENT_DEFINE_BEHAVIORS, function (DefineBehaviorsEvent $event) {
      $event->behaviors[$this->id] = ElementSeoBehavior::class;
  });

The results in
Method CraftCms\Cms\Entry\Elements\Entry::getSocialTitle does not exist., which is a method from the ElementSeoBehavior class

I haven't updated the plugin to use any of the new classes yet, justing working with the adapter for now.

Craft CMS version

6.0.0-alpha.1

PHP version

No response

Operating system and version

No response

Database type and version

No response

Image driver and version

No response

Installed plugins and versions

[linear-code]

CMS-2063