CotEditor is a lightweight plain-text editor for macOS. CotEditor is exactly made for macOS. It looks and behaves just as macOS applications should. CotEditor launches so quick that you can write your text immediately when you want to. CotEditor is developed as an open-source project that allows anyone to contribute.
Features include Syntax Highlighting, Split Editor, Powerful Find & Replace, Character Inspector, Setting via Click, Scriptable, Auto Backup, Incompatible Characters, Outline Menu, CJK Language Friendly and more.
Download: CotEditor 3.9.7