InventoryStore::purgeEffect() removes only first effect with argument ID
I created a test plugin, in which Fargoth's ring has two Invisibility effects. An engine only purges the first Invisibility effect, when I attacks someone with the ring equipped.
I think this "break" instruction causes the bug: https://github.com/OpenMW/openmw/blob/master/apps/openmw/mwworld/inventorystore.cpp#L941
(RM-3839 from redmine: created on 2017-04-23 by Andrei Kortunov, , closed on 2017-05-07 by Andrei Kortunov)
Attachments: PurgeEffectTwoInvisTest.esp