The version of Kint changed from 2.x branch to the 3.x branch. While renaming Kint class will get rid of that error, there still might be other errors you get in development due to the version differences. However, Kint never runs in production so if you've already got a site deployed it shouldn't cause any issues. Always better to be safe, though, and copy the files from the 4.0.2 repo (ThirdParty/Kint) over to your project.
