The discussion thread title was "The biggest contradiction in Islam (Answer this Musilms)", in the Everybody Draw Mohammed Day! Facebook Group.
12 pages of intense debate suddenly disappeared. I copied a post, to paste it into my response in another tab, when I switched tabs, I found the News Feed instead of the debate.
Everybody Draw Mohammad Day was the last survivor of three cartoon groups which had been the subject of a Muslim boycott of Facebook and a Pakistani isp blockade order. One Muslim had posted assertions that Islam does not allow raping captive women and another asserting that Islam prohibits child marriages. I had answered the former with chapter & verse and was in the process of posting an answer to the second when the group was deleted.
Another participant and I had previously posted a great deal of information and many useful, informative links to Islam's canon of scripture, tradition, exegeses & jurisprudence, having spent considerable time assembling that information to help other participants learn about the subject. Now all that hard effort is vaporized because of Facebook's submission to the cult of bigotry & intimidation which threatens litigation & violence.