Currently, Litmus forces pod experiments to be performed at namespace level. In case the user does not define any namespace in his chaos-scenario, the chaos-operator defaults to the "litmus" namespace, which makes it impossible to attack pods at cluster level.

I suggest the following changes:

• Remove the chaos-operator functionality that sets by default the namespace "litmus" as the target in case namespace is not defined.
• As this change could generate risks to the user when executing certain experiments, I would modify the frontend to show a warning message in case a namespace is not defined (or even set the annotationCheck to true by default when this happens).