When I create a configuration in Jenkins for a GitHub organisation and in that organisation I have a number of projects (who's configurations are automatically created and read-only within the Jenkins UI), there does not seem to be any way to exclude named branch(es) of some named subset of project which should not trigger a build.

For example in GitHub organisation widgetco there are projects for widget1, widget2 and widget3.  For all three projects, the master branch is where PRs are merged to and for all projects except the first one, a build should be triggered when a PR is merged to master.

However for project widget1, builds on merge to master should be suppressed and instead the Jenkinsfile in widget1's master branch will specify a cron task to build the branch 2x daily.

There does not seem to be any way to express this configuration.

There are hacks like skipping through the stages of widget1's Jenkinsfile but that still leaves a job in the job history where nothing was actually done.  One then has to hunt through this history looking for jobs that actually did run (on the cron schedule) vs. jobs that didn't do anything because their stages where skipped.  The job history should not be polluted in this way.

How should this problem be approached given the current capabilities of this plugin?