This page says:
retagmenu option under the post.
But the only options I see are
flag. Where am I going wrong?
When you have the privilege of editing a post, or suggesting an edit, the "retag" link is not shown. This is true for:
For example, on Ask Different my reputation is lower than 2000, and for a question asked from somebody else, I see the "retag" link.
On the same site, I don't see the "retag" link for my own questions.
On Seasoned Advice, my reputation is higher than 2000, and I don't see the "retag" link. I just use the "edit" link to edit the tags.
On sites where I am a 10k (or 20k) user, I can use the inline tag editing.