New online notifications blocks data privacy user deletion

[rolfschmidt]

Infos:

• Used Zammad version: 5.0
• Installation method (source, package, ..): all
• Operating system: all
• Database + version: all
• Elasticsearch version: all
• Browser + version: all

Expected behavior:

• User should get deleted.

Actual behavior:

#<ActiveRecord::InvalidForeignKey: PG::ForeignKeyViolation: ERROR:  update or delete on table "users" violates foreign key constraint "fk_rails_bc45d196c5" on table "online_notifications"
DETAIL:  Key (id)=(4) is still referenced from table "online_notifications".
>

Steps to reproduce the behavior:

• A heavy used user will get new online notifications while he is getting deleted. The user should get disabled first to prevent unnecessary online notifications which block the final deletion of the user row.

Yes I'm sure this is a bug and no feature request or a general question.