Hi! @PitaJ thank you for the quick reply. I understand that an absolute URL have the protocol, but most of the normal users, at least in our forums, don't know what that is, some use it just because the copied from the browser, but sometimes a user doesn't add it, and having that links as relative URL returns a 404, causing a bad experience. Some CMS have a sanity check like Django and WordPress if you add a link inside a WordPress, they check if it's another domain and adds the protocol, so the user doesn't have to add it. I think it's a good measure to prevent bad user experience.

Sorry for the very late reply @julian ! yes I was rebuilding the templates, it was a misconception by my side, i thought that I could change on the ACP the header and footer and it will affect to the other templates, but i was importing the src template. Now i'll try to override the e-mail templates using my child theme, is it just create a e-mail folder inside my templates folder? i've seen that this has been asked before, but why can't you change the e-mail subject from the ACP? i had to modify it on the src template. Thank you very much!!

@Enrique the main problem you seem to be having is that you are not aware that there is a frontend and a backend to NodeBB. You have to wire up the controls from the ACP and make a call to the backend (via websocket, for example), and then you can call server side libraries.