Thanks for the quick answer. I already tested this. The modification work "outside" the campaign. When we are modifying the workflow in the operation directly, this does not affect the starter.
When someone else wants to start my workflow (created by me under my operation), in the log part the user mentioned as starter is me. I would like to know if there is something to do to avoid this ?
We should have the "real" starter and not the creator of the workflow/campaign as starter in...