Kdenlive is excellent. Probably top of the line in terms of features when it comes to FOSS and just works unlike the probably-better-in-theory freeware alternative on Linux, DaVinci Resolve.

I recently tried iMovie on the Mac to see how it is, just wanted to cut a clip out of a YouTube video I downloaded, and while its interface is much more well integrated, it completely froze during import of the video (I think it tried to transcode it in the background and ended up swapping hard because believe it or not Apple, there actually are workloads you need a lot of RAM for). Kdenlive didn't struggle at all on the same machine.