In a Workflow build, if you use certain resources in >1 node, you get duplication of the links in the left navigation pane when you look at the info page for a build that has already run. To reproduce, install the Workflow plugin, create a new Workflow job, and give it a configuration like:
Each time you use the git resource within a new node, it causes duplication of the nav items as shown in the attached screenshot. This issue is not confined to the workflow+git combination. I have also seen it with the 'Show Build Parameters' plugin, where there is duplication of the Parameters link in the nav pane, but I can't seem to reproduce that issue consistently. I suspect that other plugins which add something to the nav field on a per-job basis could have similar issues.
I'm attaching a support bundle from my MacOS test Jenkins server, and also a build.xml that shows the issue.