Working with activities has many benefits if you work on a lot of projects. As I got to do that on a daily basis, I am seeing a number of use cases for an option that lets the user set a script before the user triggered switch to another activity.

I like to stress that it should happen before the switch takes place as there are dbus events being triggered when the switch takes place.

Examples are:

* Unlocking some container that contains files associated with the activity to switch to
* Trigger automatic update of some local files from an on-line resource
* Trigger backup of files in the present activity
* Locking some container that contains files associated with the current activity (which may require to save some open files first)
* Opening/closing applications that are not aware of the plasma activity concept

... perhaps you know some more.

In these cases is important that the command is finished before the switch takes place since files application that have files open will otherwise show old versions or fail to show the file since it is not accessible.

Probably this can be done by adding a setting to the activity manager plasmoid (which I did not find a separate bug section for).