This is indeed awkward: categories are automatically mapped to integers starting at 0, so your "1" category is actually at x=0. On the other hand, annotation x positions are always interpreted as numbers, so your x="1" annotation is in fact placed at x=1.

We don't have a good workaround for this at the moment, sorry.

cc @alexcjohnson we were just talking about this the other day :)

I see. I confirmed that works. Thanks!

Hi - we are trying to tidy up the stale issues and PRs in Plotly's public repositories so that we can focus on things that are still important to our community. Since this one has been sitting for several years, I'm going to close it; if it is still a concern, please add a comment letting us know what recent version of our software you've checked it with so that I can reopen it and add it to our backlog. Thanks for your help - @gvwilson