[flagged]
Also, for what it's worth, Jenkins changed their terminology to use "agent" instead of slave in 2020 [0]. These efforts might seem futile in isolation, but they add up over time.
[0] https://www.jenkins.io/blog/2020/06/18/terminology-update/
The comment I'd make is that this appears to have been settled nearly eight years ago in this particular context, and that maybe you should give it a rest.
The good news is that "master vs mainline" was so embarrassing that even the people who push this stuff realized they overreached and have settled down since.