4.3 What is different about Emacs 25?

• Emacs can now embed native widgets inside Emacs buffers, if you have gtk3 and webkitgtk3 installed. E.g., to access the embedded webkit browser widget, type M-x xwidget-webkit-browse-url.
• Emacs can now dynamically load external modules compiled as shared libraries.
• C-x 8 has new shorthands for several popular characters, type C-x 8 C-h to list shorthands.
• A new minor mode global-eldoc-mode is enabled by default, and shows in the echo area or in the mode line the argument list of the Emacs Lisp form at point.
• On text terminals that support the “bracketed paste mode” EMacs now uses that mode by default. This mode allows Emacs to distinguish between pasted text and text typed by the user.
• Emacs 25 comes with data files imported from the latest Unicode Standard version 9.0.0.
• The support for bidirectional editing was updated to include all the features mandated by the latest Unicode Standard version 9.0.0.
• Search command can now perform character folding in matches. This is analogous to case folding, but instead of disregarding case variants, it disregards wider classes of distinctions between similar characters, such as matching different variants of double quote characters, ignoring diacritics, etc.
• The Emacs Web Browser EWW was extended to render text using variable-pitch fonts, and got other new features.
• Rmail can now render HTML mail messages, if Emacs is built with libxml2 or if you have the Lynx browser installed.
• VC now has basic support for push commands, implemented for Bzr, Git, and Hg.
• Hide-IfDef mode now support full C/C++ expressions in macros, macro argument expansion, interactive macro evaluation and automatic scanning of #defined symbols.
• New package Xref replaces Etags’s front-end and UI. Xref provides a generic framework and new commands to find and move to definitions of functions, macros, data structures etc., as well as go back to the location where you were before moving to a definition. It supersedes and obsoletes many Etags commands, while still using the etags.el code that reads the TAGS tables as one of its back-ends. As result, the popular key bindings M-. and M-, have been changed to invoke Xref commands.
• The new package Project provides generic infrastructure for dealing with projects.
• Emacs can now draw horizontal scroll bars on some platforms that provide toolkit scroll bars, namely Gtk+, Lucid, Motif and Windows.

Consult the Emacs NEWS file (C-h n) for the full list of changes in Emacs 25.