Module development and code questions

I have a few custom entities defined by a custom module. One entity called, 'scene' contains an entity reference field to another entity called 'placed_asset'. When a user is editing or adding a new 'scene' entity, they can also add a new 'placed_asset' entity via the inline complex widget.

I am new to drupal and running drupal 7. What setting do I need to change to avoid customer ordering out of stock items. Currently its causing a lot of issues as I have to call customers manually to inform them for a replacement or a refund. 

I have trouble making AVIF compatible with Drual 11.

Thought it is natively supported, but in node editor's image upload, I cannot see AVIF in available image type list.

I tried to add it to 

I spent a whole day trying to display a url query from a view with exposed filters that would display the names of the terms instead of their IDs. Only to discover that the only way to do this is to enter the referenced field as a required relation in 'relations' and the same field again as an exposed filter, specifying the filter identifier of the referenced field.

Great, but there's the small problem that the exposed filter is a plain text field, which is of little use to a user.
So I try to turn this text field into a drop-down list.

Hi there, 

I'm working in a module to alter a form (bee reservation form) and i want to send emails to node author and email address from the form.

At this time, a can alter the form (OK), stock the fields values in session, but no way to send emails....

This is my code with e lot of logs alerts. It stops in "Stored form values in session..." notice.

Hello.
I configured ckeditor5_mentions module, it works when creating an article and when editing, but it doesn't work with comments. Can anyone know what could be the reason? There are no errors