We're also recently seeing this error, although the changes are persisted. The logs indicate an issue with the parameterized trigger plugin, which we recently upgraded to 2.40. Issue is present in 2.39 as well. I can't go further back than that as there are plugin dependencies.
java.lang.IllegalArgumentException: Unable to convert to class hudson.plugins.parameterizedtrigger.BlockingBehaviour
at org.kohsuke.stapler.RequestImpl$TypePair.convertJSON(RequestImpl.java:742)
at org.kohsuke.stapler.RequestImpl.bindJSON(RequestImpl.java:479)
at org.kohsuke.stapler.RequestImpl.instantiate(RequestImpl.java:788)
Caused: java.lang.IllegalArgumentException: Failed to convert the block parameter of the constructor public hudson.plugins.parameterizedtrigger.BlockableBuildTriggerConfig(java.lang.String,hudson.plugins.parameterizedtrigger.BlockingBehaviour,java.util.List,java.util.List)
at org.kohsuke.stapler.RequestImpl.instantiate(RequestImpl.java:790)
at org.kohsuke.stapler.RequestImpl.access$200(RequestImpl.java:84)
at org.kohsuke.stapler.RequestImpl$TypePair.convertJSON(RequestImpl.java:679)
We're also recently seeing this error, although the changes are persisted. The logs indicate an issue with the parameterized trigger plugin, which we recently upgraded to 2.40. Issue is present in 2.39 as well. I can't go further back than that as there are plugin dependencies.
java.lang.IllegalArgumentException: Unable to convert to class hudson.plugins.parameterizedtrigger.BlockingBehaviour
at org.kohsuke.stapler.RequestImpl$TypePair.convertJSON(RequestImpl.java:742)
at org.kohsuke.stapler.RequestImpl.bindJSON(RequestImpl.java:479)
at org.kohsuke.stapler.RequestImpl.instantiate(RequestImpl.java:788)
Caused: java.lang.IllegalArgumentException: Failed to convert the block parameter of the constructor public hudson.plugins.parameterizedtrigger.BlockableBuildTriggerConfig(java.lang.String,hudson.plugins.parameterizedtrigger.BlockingBehaviour,java.util.List,java.util.List)
at org.kohsuke.stapler.RequestImpl.instantiate(RequestImpl.java:790)
at org.kohsuke.stapler.RequestImpl.access$200(RequestImpl.java:84)
at org.kohsuke.stapler.RequestImpl$TypePair.convertJSON(RequestImpl.java:679)