You can select the context you want the Job design to be executed in.
Click the Run tab, and in the Context area, select the relevant context among the various ones you created.
If you did not create any context, only the Default context shows on the list.
All the context variables you created for the selected context display, along with their respective values, in a table underneath.
To make a change permanent in a variable value, you need to change it on the Context view if your variable is of type built-in or in the Context group of the repository.