[4.0] Creating a new admin menu leads of php notices

[PhilETaylor]

Steps to reproduce the issue

Login to Joomla 4 admin as super admin

Menus -> Manage -> Select Administrator from dropdown

Click New - Set title = asfjkdhcksjdfyb - set unique name asfjkdhcksjdfyb -> click save and close

Click "Add a module for this menu" button

Give module a title - select position = menu [menu] click save and close

(The first time there was a link about "menu recovery mode" that I clicked, the second time this never showed)

Expected result

No PHP Notices

Only ONE of the default menus

Actual result

Notice: Undefined property: Joomla\CMS\Menu\AdministratorMenuItem::$element in /var/www/html/administrator/modules/mod_menu/src/Menu/CssMenu.php on line 313

And if I scroll down I see another default set of the menu system with "menu recovery" hide/show link

System information (as much as possible)

Joomla 4 beta 1

[infograf768]

(4.0-dev)
Looks like you forgot to say if you have or not chosen a preset when creating the menu or the module and which preset.

[infograf768]

If I do not select a preset, I do not get your errors.

[infograf768]

There are other problems concerning admin menu creation: if one uses a preset (joomla or alternate) when creating the menu (and then that menu in the module instead of a preset), then if you need to delete some menu items through the menu items interface it takes ages to TRASH the menu items in that menu as we get into a loop (also problems with actionlogs...)
Then Empty trash is real broken. Only way is to delete the menu.

Remark that editing the menu itself does not display anymore the preset used. It is confusing.

[infograf768]

Sorry, confused about this

Select MyBrokenMenu under Administrator in the left menu

as it comes after

Click "Add a module for this menu"

as we are in a modal

But if I ignore this I do indeed get all these Notices from the module in the menu position because the Menu has no menu items (no presets were chosen when creating the Menu and same when creating the module) and CheckMenu was set to Yes.

I guess the solution would be to throw an error somewhere. We just have to find where.

[infograf768]

btw, I confirm

(The first time there was a link about "menu recovery mode" that I clicked, the second time this never showed)

[brianteeman]

This bug is caused by #23452 which probably should not have been merged due to lack of tests