It is convention that the Jenkins UI should not use the configured root URL, instead looking at the request to build up links.

This convention is not followed in https://github.com/jenkinsci/cloudbees-folder-plugin/blob/b3bb87403f6503410cc5dc45c4445c007984f188/src/main/java/com/cloudbees/hudson/plugins/folder/AbstractFolder.java#L832 resulting in potentially invalid links in the children context menu of folders (which links to views).