TinyMCE is not working for mobile view in Google Chrome using "tinymce-rails" gem

Question

I have added "gem 'tinymce-rails'" in my rails application I have added "//= require tinymce-jquery" in my application.js

And in my js.erb file, I initialized it using

tinyMCE.init({
  selector: '#offer_description',
  menubar: false,
  branding: false,
  height: 300
});

and on edit, I reinitialized it using

tinymce.EditorManager.execCommand('mceRemoveEditor',true, (tinymce.EditorManager.activeEditor != null) ? tinymce.EditorManager.activeEditor.id : null);

tinymce.EditorManager.execCommand('mceAddEditor',true, (tinymce.EditorManager.activeEditor != null) ? tinymce.EditorManager.activeEditor.id : null);

And in my view page, I have added class "tinymce" like this:-

= form.text_area :description, :maxlength => "5000", :class => "listing_description_textarea tinymce"

It is working fine in both firefox and google chrome. But in mobile view in Google Chrome, it is displaying a black box having a book icon in middle and the text area is not working. There is no error in the browser console and Ubuntu Terminal. What should I do to get it work properly?

This error is displaying in mobile view in place of tinymce Text Editor