As it is written above, stealing somebody's ideas is a plagiarism, too, and havethere is no excuse.
I would do the following.
- Write anto the editorial board, show them your case and ask them to withdraw the paper orby the plagiatorplagiariser.
- If this fails, write to the publisher stating that the editorial board of their editorial ignoresjournal ignored you about the plagiarism case.
- If this does not work, go to court against the publisher. Try to highlight your case in press and social networks as widely as possible.
I strongly believe that this should be well enough, no serious publisher would like to have reputation spots like this.
I should add, that people behave like this in science mainly in societies where such a behaviour - to steal smthsomething from smbsomebody who is weaker than you - is generally common (like in Russia).
Particularly, I had my own case like you described, but was lucky - the paper written after reading my mscrmanuscript by a reviewer came, vice versa, to me for revision. So I wrote to the editor about the situation providing proofs. The plagiatorplagiariser is now likely in the black list of several large international publishers, as they published 0 papers in international journals after this. But I also saw examples when older academics ruined the careers of younger colleagues by stealing their results. You should never go to peace agreements with such people,people; they must meet the resistance and must be punished for what they do. Their normal business is either to steal as much as the victim allows by its own silence or to persuade the victim to pass his results by own will.
Make youyour voice loud and do not feel ashamed about making problems for the careers of plagiatorsplagiarisers / do not be afraid to conflict with them! People behaving like this do not understand good will, but they respect only strength.