The following messages are empty in en.json:
i18n/en.json: "flow-rev-message-edit-post-contributions": "",
i18n/en.json: "flow-rev-message-reply-contributions": "",
i18n/en.json: "flow-rev-message-new-post-contributions": "",
They all have qqq documentation, which specifies parameters. More importantly, they seem to be actually used:
https://he.wikipedia.org/wiki/%D7%9E%D7%99%D7%95%D7%97%D7%93:%D7%AA%D7%A8%D7%95%D7%9E%D7%95%D7%AA/132.64.44.72?uselang=qqx
As you can see on that page, the bottom two entries, from 14:09, 28 (march) 2015, are about creating a post and about replying, but if you look at that page in English, you'll see that the text of the two lines is the same (except "hide / hide topic" in the end). I'd expect them to specify that one is a topic creation and another on is a post.
See also T93977