Problem with non-english languages

This plugin is not Working with non-English languages. If your titles are written in languages like Farsi, the anchor link will be something like i-1.
The problem is in the url_anchor_target method.
You are removing all characters those are not in English. I solved this problem for my self by adding Persian Unicode characters in the preg_replace pattern. But it’s hardcoded and is not a good solution.
I think you can solve this problem by simply adding another field to the plugin settings page to users add their additional patterns or selecting their languages.
Unfortunately, I did not find any link that shows your code is open source to contributing in it.
So I hope so you solving this problem yourself.
Thank you.