It is necessary to prevent or warn the developer if references to config data is altered at runtime?

[stefanhaerter]

While investigating #1447, I figured out that in Kernel/Modules/CustomerTicketZoom.pm, while fetching the process activity information, a reference to the config data is edited, which then edits the config itself instead of a copy of the data.

As a reminder for the future, I open this discussion with the question if we somehow want to prevent such probably unintended behaviour, e.g. in the code policy.