One of our developers noticed that our PC-Lint warnings trend graph only showed builds from the last 30 days and that configuring the graph to show more had no effect.
I noticed while debugging this that the cookie being generated to save the trend graph configuration had the wrong path set so that the project dashboard wasn't loading it. The path was being set to the URL of the trend graph's configuration page (ex. http://jenkins/project with spaces/warnings0/config). If I manually edited the cookie's path to point to the project dashboard (ex. http://jenkins/project with spaces/) it worked. The same issue exists if a project dashboard is opened from a view with spaces in the name (ex. http://jenkins/view/View with spaces/Project_with_underscores).
Near as I can tell the source of the issue is in CookieHandler.java:
I think this line of code is the culprit which returning the wrong URL for the cookie's path.
Ancestor ancestor = requestAncestors.get(requestAncestors.size() - ANCESTOR_PATH_PREFIX);