Let me try to capture the comments in an answer.
If you work on something and your work appears in a paper, then, ethically, you are an author of the paper and no one can, properly, deny that.
If you are an author of a paper, then, ethically, your permission is needed to publish it.
Those are the accepted rules, but they are sometimes broken. I don't know how much you trust your advisor to behave properly. Most will, but some will try to cut corners and a few are unethical. Sometimes that arises from desperation to publish themselves.
I find it odd (disturbing) that the advisor won't let you see the email from an editor. This is a red flag. But asking to extend the deadline isn't problematic in itself. Perhaps the advisor thinks the paper needs more work or is hoping to get your participation.
In many ways it would be better if you don't drop out of the project altogether, but suggest that other commitments require you to spend minimal time on this one. That keeps you connected, at least, but doesn't require a big commitment. Thoughts more than time, perhaps.
But if you truly feel at risk and don't feel you can trust the advisor, then reminding the editor of the facts of the case might be wise. Don't make accusations, but just note to the editor that the work is based on your dissertation and that, properly, you are an author with an interest in the work.
Also, if you are not in academia or have switched fields, then it would also be wise to give permission to publish as long as you remain a co-author and approve of the work generally.
But also note that if the work has been extended, and the main results are no longer yours, then you might not have a claim at first authorship of the result. That may matter only a little or a lot, depending on your current situation.