I attempted to reproduce the issue using your docker image by following steps 1-2 and then created my own pipeline project based on the first two images that I have attached in the bug description. The github hook trigger didn't even go through so I am inclined to assume that Github hook trigger does not function properly in this setup/environment to begin with (or at least some part of the flow is broken).
In addition, when you tried to reproduce the issue related to multiple branches triggering from one branch, you used "multi-branch pipeline". I should've mentioned, if I haven't already, that I am using a standalone pipeline specifically because it does not support Github hook trigger...
As for the issue related to "polling ignore commits.." functionality, my project is configured to push a new commit to the SAME branch after a successful build. Theoretically, this should repeat indefinitely UNLESS otherwise configured, hence, I had "polling ignore commits.." enabled to ignore the commit based on specific values. But in you're docker image, the Jenkins project setup does not have this configuration enabled. The steps followed to reproduce this issue does not seem like a very good simulation to recreate the original problem.
If there is anything unclear in my comment, please let me know.
Neuronal T Do you have any insight in this whole thing? Have you found any workaround?
I'm an idiot. Of course the webhook from github won't work because I didn't have it set up..But I would like to re-iterate that the steps followed, in my opinion, do not seem like a good way to reproduce the issue.
Sadly, I am not sure if there is an easier way for you to reproduce the issue besides setting it up the way I did. Is there anyone else that you know who might be able to help or have an environment setup up similar to mine?