I'm afraid that the language used by the HTML generator is based on locale. While you may be able to edit the callus.js file, that'd be at your own discretion.
Hi @VasilisV_3CX maybe we have a missunderstanding. My post is not about the language, it is about the fact that the red marked popup is not appearing on out side.
Thanks @VasilisV_3CX. I tested again today and suddenly the greeting was visable. Maybe some caching problem. So looks like all is working as expected for now.