I found that, when I delete the second and other posts, it can be “undeleted” , but if I accidently miss-deleted the first post, it will not be allowed to “undelete” the post any more.
What if I just miss-deleted the first post of the full page?
My discourse version:
That has just cropped up in another topic. You should be able to un-delete a topic using these UI elements:
I’m upgrading my test site now to see if something has gone awry. 
I’ve just upgraded (940eb0ce4d) and it seems to be working fine for me. I am not sure why yours is missing?
Hello,
I think this is happens when a user self delete the topic (OP).
I created a topic with a non-staff (TL1) user and than delete it with this user. This user can undelete the topic OP with clicking the 
icon.
But in this situation staff users can’t see the undelete icon. And I think this is because the user decided to delete the topic and there is no reply yet so user free to delete it.
There is only a wrench button which is also not contains undelete…
And the topic actions buttons also not contains.
If this is the case I think the only way to undelete the topic OP from staff side is open the topic and revert the topic history.
I’ve just had a quick go at this @Don, and based on the screenshot in the OP [1] the icons are red, so it means that the post has been deleted rather than at the ‘visible but (topic deleted by author) stage’.
Once it’s been deleted I can see, as admin, the un-delete options as normal:
Though if it’s still at the visible ‘(topic deleted by author)’ stage then it hasn’t been deleted yet and counts as a post edit, in which case you’d be right. 
Ah yes you right 
but you can only undelete to the (topic deleted by author) status.
I don’t know what scenario cause this. 
