Why can't I comment on other replies?

Is this a bug? I cannot comment on any replies other than my own. The add comment button is simply not present on other posts. Am I missing something- or what? I will delete this post as soon as I can get an answer ( I know this question probably doesn’t belong here)

Thank you!

You cannot comment on other people’s posts until you reach at least 15 reputation from what I remember. And I wouldn’t delete your question. It might be useful to somebody. You should mark an answer correct though so people know the solution.

I had a similar problem yesterday where I couldn’t even comment on my own question in Chrome, but I could in IE. So it could be a browser issue. However, today I do see the “add new comment” button on this post in Chrome, so I dunno.

I had to enable 3rd party cookies to be able to reply (urgh :))