I'm on 5.0.5 and if I have a thread with, say 5 or 6 posts in it, if I select the checkbox for even just 1 of the posts and then choose "Delete Posts", the deletion box that pops up says I'm deleting X number of posts (X = however many posts are in the entire thread - NOT just how many I've selected with the checkbox). Then if I click to delete posts, then the entire thread is deleted - not just the 1 post I selected. Am I missing something?

See attached screen shot. 2 posts in this thread, one is selected for in-line moderation, but the deletion notice is saying 2 posts will be deleted.