XEmacs is fork of GNU Emacs, providing much of the same functionality. XEmacs development is stagnant.
XEmacs is a fork of GNU Emacs, created in the late 1980's with an emphasis on incorporating "modern" editor capabilities (colors, images, menus, etc.). Most of the functionality originally available in XEmacs is now available in GNU Emacs, and development of XEmacs appears relatively stagnant.
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