Kdenlive

Kdenlive is a powerful, free, and open-source video editor based on the MLT framework. It offers a surprisingly professional feature set, including multi-track editing, proxy workflows for 4K, a wide range of effects and transitions, and keyframeable audio mixing. It's a flagship editor for the Linux community but also available on Windows and macOS. It ranks highly for budget-conscious creators, open-source advocates, and Linux users seeking a fully-featured, donation-supported NLE without watermarks or export limitations, backed by an active development community.