Looks like this is abandoned ... but there isn't actually any other option for Xdebug w/ Atom.
I have it 'working', but that's a loose definition since there's some weird side effects happening that I'm unsure if they are caused by Xdebug3, or this repo, or the atom-debug-ui ...
Came here to file the bugs/errors ... and wondering if it's worthwhile. Tagging @gwomacks and @cchamplin to see if there's any response. :-/