In my company, we use github enterprise on premise and a lot of jenkins for many department. That is, there are multiple jenkins masters here.
To use github oauth plugin, people have to make their application in github to get their clientId and client secret per jenkins master. But I think it is redundant.
If we can use "redirect urls" of github oauth, we don't need to make that many jenkins applications in github. You can find more information here
To be specific, we can set different redirect uri in each jenkins master for their "finish login url" with same client ID and client secret. Then we just need one github application for the client ID and the client secret.
However, it seems not possible to set redirect uri with github oauth plugin. So I could change it to support multi-master jenkins.