While checking out the latest Witcher 3 secrets from xLetalis, I came across something that startled me: The Witcher 3 has its very own Unofficial Patch-style mod, Brothers in Arms, that not only gets after persistent bugs left in the nine year-old game, but also restores some minor cut content to boot.
A great preponderance of the bug fixes are the sort of things a lone player might never notice: journal typos or missing text fixed here, Witcher sense clues scrubbed from the open world after quest completion there, you get the idea. Taken all together though, these thousands of minor bug fixes from multiple mod authors add up to an even more consistent, polished game.
The cut content is definitely the most interesting stuff though, especially since much of it blurs the line between bug fix and restoration. Take my favorite that I've noticed so far: a bit of dialogue with Temarian spymaster Thaler that wasn't "cut" from the game, so much as the flag it relies on just wasn't working. With that issue taken care of, you now get dialogue options with Thaler that confirm his connection to the "A Frying Pan, Spick and Span" quest from White Orchard.
On the more minor side, Geralt can finally snack on delicious, nutritious bell peppers. Not only was the fruit extant in The Witcher 3's files, its health restoration effect was even tweaked in the next gen 4.0 patch. Brothers In Arms merely restores this perfectly acceptable foodstuff to its rightful place in The Witcher 3's loot tables, so now when Geralt runs out of Swallow potions he can munch on raw bell peppers and wolf's liver to heal up like the weirdest kid in the cafeteria.
I also noticed restored minor dialogue for major NPCs like Keira Metz, Triss, Avallac'h, and Vesemir, as well as for any number of unnamed quest givers and NPCs. The most important change of all, though, is that the Skellige Gambeson is finally back, baby. This decent early game light armor has seen me through to buying the far sexier Temarian set in many a playthrough, and now it finally has its original, vaguely Bavarian coat of arms-esque, white and baby blue color scheme. CDPR swapped it for a vomit green coat of paint sometime after launch, and it's always made me feel like I had been gaslighted by the company. Finally, justice for the Skellige Gambeson.