What happened?

Description

NOTE: This issue affects Craft 4 and Craft 5

I have created a Structure with Max Levels set to 2. If a top level entry (level 1) has a child entry it should not be possible to drag it below another level 2 item as it will generate a third level. As per the image below if Top B is dragged below Top A it is blocked correctly.

However, if on the above scenario, the Top A entry is collapsed, as per the image below, then it can be moved.

This then results in a Structure that is 3 levels deep which should not be allowed. Subsequently a 3 levels collapsed structure can be dragged again to create a 4 level deep structure, etc.

Steps to reproduce

1. Create a Structure with Max Levels = 2
2. Follow the images above to reproduce the issue.

Expected behavior

It should not be possible to create a 3 level deep structure by dragging. The Move should be blocked.

Actual behavior

Multiple levels can be created by dragging a collapsed structure.

Craft CMS version

5.2.5

PHP version

8.2.20

Operating system and version

Linux 6.5.0-42-generic

Database type and version

MySQL 8.0.36

Image driver and version

No response

Installed plugins and versions