A browser plugin was removed from one of the app stores last year as it had stopped working, and the author was no longer maintaining it in favor of their standalone desktop apps. I preferred using the plugin so I forked the repository on GitHub, made some changes so it worked again, and re-published it on the app store.
The source code repository said the project was licensed under Apache 2.0 which led me to believe I was free to modify and distribute the software as long as I retained the copyright notice and kept track of all the changes I made. To fulfil this obligation I made it clear in the app store description that I was not original author and linked to the GitHub fork repository where the licence and changes could be found.
About 6 months after publishing the package I received a DCMA Takedown Notice via the app store operator. The authors say I am infringing on their copyright and listed their desktop app as the copyrighted work that I am infringing on (which are not open source).
Has the author lodged an improper DCMA takedown request in this case?