new mobile detection code for image iframe

Author: felliott

mfr/extensions/image/templates/viewer.mako

@@ -53,7 +53,8 @@
  $(document).ready(function() {
 
  ## Reference on how mobile is detected: https://stackoverflow.com/a/10364620
- var isMobile = window.matchMedia("only screen and (max-width: 760px)");
+ ## var isMobile = window.matchMedia("only screen and (max-width: 760px)");
+ var isMobile = window.innerWidth <= 768;
 
  ## Enable the zoom feature only for desktop browsers
  if (!isMobile.matches) {