According to /u/Spez, Reddit CEO, the reports of messages edited without any user consent or knowledge are correct as he admits to have done it so himself:
Hey Everyone,
Yep. I messed with the "fuck u/spez" comments, replacing "spez" with r/the_donald mods for about an hour. It's been a long week here trying to unwind the r/pizzagate stuff. As much as we try to maintain a good relationship with you all, it does get old getting called a pedophile constantly. As the CEO, I shouldn't play such games, and it's all fixed now. Our community team is pretty pissed at me, so I most assuredly won't do this again.
Fuck u/spez.
The edits were made in a thread linked from the Washington Post which described the recent ban of the /r/pizzagate subreddit which tried to uncover child-molesters and recently moved to voat.co.
(Score: 0) by Anonymous Coward on Saturday November 26 2016, @11:11PM
Thank you. I get the high level idea here, namely that admin people alter posts, but I still don't know what the hell spez nor pizzagate are from the summary.
(Score: 2, Informative) by Anonymous Coward on Saturday November 26 2016, @11:17PM
spez is the username of the reddit ceo
pizzagate is another bullshit conspiracy theory about clinton and pedophiles centered on a pizza restaurant in DC
the neonazis have a million of these tedious conspiracies and every once in a while they go full retard and pile on, pizzagate was just the most recent pile-on, it happened on reddit and there were a ton of terms of service violations, the conspiracists tend to be unhinged anyway so enforcing the TOS gets them even more worked up. the ceo just added fuel to the fire
(Score: 0) by Anonymous Coward on Sunday November 27 2016, @12:34AM
Excellent, thank you for your reply.