Add default service providers in configuration

[Yoji]

It would be nice to add the ability to replace and extend standard service providers in the configuration file.

For example, I need to extend the standard UserFactory, but I can't replace it before starting the Application and creating the container.

[laoneo]

You should be able to write a system event and then listen to the onBeforeExecute event and then set it on the container.

[Yoji]

You should be able to write a system event and then listen to the onBeforeExecute event and then set it on the container.

onBeforeExecute is a potential problem.
For example, several plugins are installed on the site that use `onBeforeExecute' and one of them uses the User provider before it was replaced

[brianteeman]

Plugins are executed in order

[joomdonation]

I don't see any chance this request will be added to the core, so please use a system plugin to handle it as suggested by @laoneo above. I will convert this to discussion so that we can discuss further from there if needed, maybe it could be good ideas for future releases of Joomla.