A week ago I deleted all my photos, friendlists , and activity logs with the APP
Add-on - "Social Book Post Manager" Chrome Extension Lets You Wipe Your Facebook Profile, I gave the button remove all at several passes mode, and facebook data was totally cleaned, but guess, guess you, what happen about with the private messages! facebook profile was cleaned with my timeline images folders , videos and all the other folders, but it does not erase the images from the private messages, WTF, and it offers them as Featured images, impossible to delete, some people in its help forums asking for a solution to that but they don't answer, that is, that Facebook secretly keeps unwanted private files chats even from previous years and after having cleaned the entire chat rooms manually, message history, old images that were sent to people who have been blocked-eliminated in the past with whom you privately chatted (couple, friends, co-workers & strangers) the images persist in featured images but they do not exist in the chat. but the question is why they keep them, why can not be deleted, and why appear in the section: change avatar or cover. I can give you an advice, do not use those websites anymore, they will suck the life of the people with a cost, and you have absolutely no right to claim, your life could be marginalized.