Electron + xmpp.js: How I can Debug SSL Self-signed error messages?

I am using a combination of electron.js and xmpp.js in order to make my own client. My main project is consisted of these 2 files: Boostrapping electron on: index.js: And handling it with this file xmpp.js: Also my ui is consisted by index.html: With the following renderer: But my problem is that when I fired up my own local opefireserver using self-signed certificates. Because of that I get a mysterious error that is displayed like that: So my problems are: How I can debug these types of errors? I mean I cannot find out the location of this error. How