found the culprit in building see-gateway the file in the source tree is a link ls -lrt src/main/resources/org/jenkinsci/plugins/ssegateway/sse/EventSource.js lrwxr-xr-x 1 olamy staff 77 13 Feb 19:45 src/main/resources/org/jenkinsci/plugins/ssegateway/sse/EventSource.js -> ../../../../../../../../node_modules/event-source-polyfill/eventsource.min.jsdifferent result there is a difference when copying resources in 2.7 and >=3.0.0 maven-resources-plugin:2.7:resources ls -lrt target/classes/org/jenkinsci/plugins/ssegateway/sse/ rw-r-r- 1 olamy staff 5226 13 Feb 21:04 target/classes/org/jenkinsci/plugins/ssegateway/sse/EventSource.js maven-resources-plugin:3.1.0:resources ls -lrt target/classes/org/jenkinsci/plugins/ssegateway/sse/total 0lrwxr-xr-x 1 olamy staff 77 13 Feb 21:01 EventSource.js -> ../../../../../../../../node_modules/event-source-polyfill/eventsource.min.js with 2.7 version of the plugin the file is copied as a file and not as a link as done by version >=3.0.0 |