VFX: It's important to set order back to original one

If your Report contains code that modify active tag of a table but you forget to switch back to the original one when it finishes, a header-detail form that has a childgrid based on that table will memorize that new active tag (and system will store it in vfxres file).
The result is the next time the form is opened, setting is retrieved from vfxres and wrong tag is used (you will see empty childgrid).