Multibranch Pipelines, push, and ignoring commits in certain paths

[Michael Lasevich]

We have a setup where git server (Stash) notifies Jenkins server via WebHook of commits in certain branches and a MB job executes builds on branches matching the change 

This works fine, but we would like to ignore changes not affecting the build - so only react to changes in certain files/directories. Git Jenkins plugin appears to offer this via "Additional Behavior" called "Polling ignores commits in certain paths" - but having this configured, it does not appear to work in this scenario (build still happens, even when the change is outside of the included paths) - Should this work and do I need to do anything else to get it to work?

I realize that plugin is for Polling and we are using WebHook/PUSH - but as I understand (and I may be wrong) webhook/push builds simply trigger immediate polling mechanism - or is this not the case with push for multibranch/pipelines?

Thank you, 

-M