problem:

The configurations on level task-import can be changed before import, but if a task is imported, they must not be changed anymore to prevent problems for example on export.

If a configuration may be changed on already imported tasks, the level is just task then.

Here we have a leak in the concept. If configurations from level task-import are not changed for a specific task, they remain on the value configured in the system config.

If the admin changes the value in the system-config, the value is changed for all tasks not having a specific value in its task-config table.

For configurations related just to the import this is no problem, since the import is done, changing such configs does not harm anything. But there are a lot configs where this could be a problem: for example "Protect Tags", "Visual: Disable WYSIWYG", "DeepL api parameter: language formality".

Additonal todo:

review all configurations <= client-level if there is a similar problem.

solution: 

Configurations of level task-import must be set always in the task_config table when a task is created. So the problem is solved, if the value is changed in the system config, it remains as it was on import time for a task.