Apps Related to Rich text editing

Sunbird was a standalone calendar application and also a Firefox extension developed by Mozilla, designed for managing events, tasks, and calendar synchronization. It aimed to provide a free and open-source solution for personal and professional scheduling needs.

Dabblet is an interactive online code playground designed specifically for experimenting with CSS, HTML, and JavaScript. It provides a live preview of your code as you type, making it an excellent tool for web developers to test snippets and share their work.

BasKet Note Pads is a versatile, freeform note-taking application for KDE that allows users to organize thoughts, manage tasks, and gather information visually. It supports various content types, offering powerful organization and sharing capabilities.

KeyNote NF is a versatile, open-source notebook application offering a tabbed interface, rich text editing, multi-level note organization, and robust encryption for secure information management.

CherryTree is a powerful, free, and open-source hierarchical note-taking application. It allows you to organize your thoughts, ideas, notes, and code snippets in a tree-like structure with rich text editing and syntax highlighting.