I was surprised to see that I can't reference github as an external tracker, and I did some searching here and didn't seen an open ticket, so... Please consider adding some way to reference a github issue as an external bug. I suppose with a naive implementation each github project would have to be added individually, which obviously wouldn't scale. But it should be possible to include the project name in the "Bug ID" that bugzilla would use, which would give you enough of a unique ID to find the issue. For example, "SpamExperts/pyzor/38", or just take the whole URL and parse it. There's enough information there to get down to https://api.github.com/repos/SpamExperts/pyzor/issues/38 for the json you need to determine the ticket state.
Github is there now, usage is "SpamExperts/pyzor/38"
This is great, thanks!
FWIW I just tried to use this feature in bug 1373295, but the ccache/ccache/129 usage resulted in a broken link. Had to use ccache/ccache/issues/129.