I have discovered the most amusing exploit ever.
Eater's Nectar Injectors are ultra-rare things that increase your stats permanently (by the way, does anyone know where to get Arsplice Seeds?)
A Booster Gun can be loaded with one injector, which it fires to hit an enemy. You can get them from certain robots in Bethesda Susa, although it's not easy (I think the easiest way is to use the axe skills to dismember them and hope they drop it.)
Temporal Fugue duplicates get copies of anything you're equipped with, including ammo. You can probably see where this is going now, but...
You can load an Eater's Nectar Injector into a Booster Gun, then equip it and use the Temporal Fugue to produce duplicate of yourself, then stand between them and the enemy. Occasionally, they will shoot you with their booster guns by accident, giving you a permanent stat boost or mutation point, without using up any permanent resources. You can repeat this as often as you have the patience for.
(In practice it is much harder to exploit than it seems -- the duplicates were not cooperative when I did it. But I managed to get them to hit me a few times, and it does work. I tried it with Evil Twin, but sadly they didn't seem interested in using the booster guns to attack -- though maybe it was because I was too close to them? Hrm. Maybe with a way to force some sort of distance, like force bubble.)
I don't actually feel this needs to be "fixed". It's incredibly obscure and requires combining a lot of different things in an odd way; you have to have Temporal Fugue and the axe tree, and you also need an Eater's Nectar Injector -- not easy to find. And at the end of the day, if someone wants to exploit such a bizarre combination of stuff, it's not really game-wrecking. But I found it amusing enough to mention it here. In theory, you could use this to get the benefit of any injector, although you'd risk being hit by more than one copy and suffering side-effects (not a problem with Eater's Nectar Injectors, which take effect immediately.)
An unrelated bug, maybe related to the cloning changes recently: I put an Eater's Nectar Injector in my thrown slot as a test, then used a cloning drought to clone myself, then used Domination on the duplicate. When I tried to unequip the injector, it was treated as if it was on the ground, not in my hand -- there was no option to unequip it, but there was an option to 'get' it. Getting it and then using it somehow resulted in me still having an injector in my inventory, which I could equip and use again repeatedly. I think the bug here affects all thrown items equipped by clones, or something of that nature.