Although the project page says Windows versions older than 10 may run packages from the GitHub archive this has failed at least so far with version 1.1.3 on Windows 7 Home Premium x64 with 0Patch Pro:
Not sure what the cause of this problem is, but Electron has dropped support for Windows 8.1 and previous versions. Only Windows 10+ will be supported going forward.
Although the project page says Windows versions older than 10 may run packages from the GitHub archive this has failed at least so far with version 1.1.3 on Windows 7 Home Premium x64 with 0Patch Pro:
https://github.com/yang991178/fluent-reader/releases/download/v1.1.3/Fluent.Reader.Unpacked.1.1.3.x64.zip