Have seen this on console when starting with cloudbees-workflow-aggregator installed. What does it mean?
... org.apache.commons.jexl.util.Introspector getMethod
SEVERE: Introspection Error : Ambiguous method invocation toNormalizedIconNameClass( null) for class org.jenkins.ui.icon.IconSet
Inappropriate use of GString
Integrated in jenkins_main_trunk #3870
[FIXED JENKINS-25499] Updated icon-set dependency to version 1.0.5 (Revision f87c72f15858edf5dd499349569497c3c2bf4449)
Result = SUCCESS
tom.fennelly : f87c72f15858edf5dd499349569497c3c2bf4449
Fixed this issue (and JENKINS-25498) in the icon-shim plugin. Updated dependency to new version of same.
Just upgraded to 1.580.1.1 and I am experiencing this message as well. Is there a loss of functionality this this error?
Possibly caused by JENKINS-25498, though the error message is so lacking in detail as to make it hard to tell.