#HTML
Sigil
Sigil is an open-source, cross-platform EPUB e-book editor supporting EPUB 2/3 standards. It offers dual modes—book view and code view—complete metadata management, and real-time preview, making it ideal for content creators and e-book enthusiasts to easily produce high-quality e-books.
SubEthaEdit
SubEthaEdit is a free and open-source macOS collaborative text editor designed for developers and teams. It supports real-time multiplayer collaboration, code folding, regular expression search, and dynamic HTML preview, enhancing programming and collaboration efficiency.
Tincta
Tincta is a free, lightweight, native macOS text editor focused on speed and ease of use, featuring syntax highlighting for over 65 programming languages, regex search, and multi-theme support. Perfect for daily writing and web development. Now an open-source project, it supports older versions of macOS.