I already have universe and multiverse repositories enabled by default.
Firefox 52 may be old, but it works - including with jitsi. I only use it on trusted sites when I need the functionality of some of my add-ons that no longer work with Quantum (Firefox 60.0+).
It looks like the most obvious error is
The given hostname does not exist in the config
I did some searching.
One thread (that you are in) mentions
That directory/file does not exist on my system.
Looked further and the main problem seems to be end user malfunction. I’m not used to using things I don’t need to install.
I found your manual install page and it’s all about servers that I don’t need.
So, I’m going to purge jitsi and just use it with Firefox and your web service when I need it.
Thanks for your efforts.
If you haven’t tried Vivaldi, it’s an amazing browser for power users. And, if you understand this stuff, you’re definitely a power user!
It’s based on chromium and is highly configurable and customizable. If you use a lot of tabs, there are tons of management features for them.
It has web panels that you can tuck away in a sidebar. You could have jitsi running in one of them and pop it on and off screen with a single mouse click or hotkey and it stays available as you switch tabs and browser windows.
Some of the people responsible for the Opera browser (up to version 12) are the ones behind Vivaldi. There’s a great community as well.