Our 8.4.1 release did not actually fix the critical "random files on your disk" issue. This had us demote the release to a "pre-release". In this release, our feature seems to - finally - be working as intended again. We also fixed an issue with the Windows installer not being able to use the default state directory.
After that bit of chaos, we now have v8.4.2 as the first "actually stable" 8.4 release.
For Mac users
Our .app signing is currently broken (issue #8835). This means that you will have to manually tell your Mac to clear the "quanrantine this app because it was downloaded from the Internet"-flag using one of the following command in your terminal:
xattr -d com.apple.quarantine /Applications/Tribler.app