FFMPEG is nice when you do something like ffmpeg -i input.mp4 -vcodec copy -acodec copy -ss 00:01:00 -t 00:03:00 out.mp4 and the result is almost instant as there’s no re-encoding.

This looks interesting. Thanks for the link!

Kdenlive, easily. The only other video editor that feels good to use on Linux is the non-FOSS DaVinci Resolve (which requires paying for you to get any practical codec support).

Some people say Blender, but those people must not work on very complicated projects…

For simple cutting & slicing I honestly just write ffmpeg oneliners.