**REPOSITORY**:  https://github.com/lawlist/buffer-menu

**CLONE REPO**:  git clone https://github.com/lawlist/buffer-menu

The porting of the Xemacs buffer-menu features to Emacs 26 resulted in the creation of a library consisting of 600+ lines of code.  Approximately 99.9 percent of the code is straight from Xemacs, with a few modifications by @lawlist where particular Lisp functions did not exist or they are somewhat different in Emacs 26.  The general format for creating a menu in Emacs 26 is a little different than in Xemacs.  Installation instructions are contained in the repository.  Here are some screenshots:

https://www.lawlist.com/images/buffer_menu_a.png

https://www.lawlist.com/images/buffer_menu_b.png

https://www.lawlist.com/images/buffer_menu_c.png

https://www.lawlist.com/images/buffer_menu_d.png