How to prevent Emacs from converting JavaScript symbols to HTML code?

Question

When I insert a portion of JavaScript code within an HTML file, Emacs convert some basic JS symbols to their HTML code. For example when I type >, Emacs convert it automatically to > which this makes it impossible to code JS.

How to circumvent this issue?

EDIT:

Here is the content of my .emacs file:

(custom-set-variables
 ;; custom-set-variables was added by Custom.
 ;; If you edit it by hand, you could mess it up, so be careful.
 ;; Your init file should contain only one such instance.
 ;; If there is more than one, they won't work right.
 '(ansi-color-faces-vector
   [default default default italic underline success warning error])
 '(custom-enabled-themes (quote (tango-dark)))
 '(package-selected-packages (quote (js2-mode green-is-the-new-black-theme))))
(custom-set-faces
 ;; custom-set-faces was added by Custom.
 ;; If you edit it by hand, you could mess it up, so be careful.
 ;; Your init file should contain only one such instance.
 ;; If there is more than one, they won't work right.
 )
(package-initialize)
(add-to-list 'package-archives '("gnu" . "https://elpa.gnu.org/packages/"))
(add-to-list 'package-archives '("melpa" . "http://melpa.milkbox.net/packages/"))
(add-to-list 'package-archives '("melpa-stable" . "http://melpa-stable.milkbox.net/packages/"))


(require 'green-is-the-new-black-theme)

(setq column-number-mode t)     

(setq-default indent-tabs-mode nil)

(setq sgml-quick-keys 'indent)

;; For JavaScript
(require 'js2-mode)
(add-to-list 'auto-mode-alist '("\\.js\\'" . js2-mode))
;; Better imenu
(add-hook 'js2-mode-hook #'js2-imenu-extras-mode)

Answer 1

This is because you've configured:

(setq sgml-quick-keys 'indent)

C-hv sgml-quick-keys tells us:

sgml-quick-keys is a variable defined in ‘sgml-mode.el’.

Documentation:
Use <, >, &, /, SPC and ‘sgml-specials’ keys "electrically" when non-nil.
This takes effect when first loading the ‘sgml-mode’ library.

As html-mode is derived from sgml-mode, this applies there as well.

Many people like http://web-mode.org/ for editing files which mix HTML/JS/CSS.