Webcomplete implementation for Emacs with Chrome/Chromium on Linux.

.emacs

(defvar ac-source-chrome-cache nil)

(defvar ac-source-chrome-complete
      '((candidates . (ac-chrome-candidate))
        (symbol . "w")))

(defun clear-chrome-cache ()
  (setq ac-source-chrome-cache nil))

(add-hook 'focus-in-hook 'clear-chrome-cache)

(defun ac-chrome-candidate ()
  (or ac-source-chrome-cache
      (setq ac-source-chrome-cache (or (split-string (shell-command-to-string "chromecomplete.py"))
                                       '("")))))

(setq-default ac-sources (push 'ac-source-chrome-complete ac-sources))

Must be combined with this script https://gist.github.com/baongoc124/ab7fab56f9f95363c75ff79b19257b60
See the demo here https://youtu.be/z_X8Wvwmu1w
Original plugin here https://github.com/thalesmello/webcomplete.vim