How to change the title of login page and point of sale page in odoo 10?

I'm trying from a week to change the "odoo 10" pages title, I found a solution in this request:

How to change the title in Odoo 10?

It suggests to edit the addons/web/static/src/js/abstract_web_client.js file and to Change this code:

this.set('title_part', {"zopenerp": "Odoo"});

With this one:

this.set('title_part', {"zopenerp": "YourPageTitle"});

It worked fine with me but the problem that the "login" page title and "odoo pos" page title haven't changed.

Can any one help me please ?.